Neonatal Vitamin K Prophylaxis

Posted in Uncategorized on September 14, 2008 by southsanjuan

The following paper on vitamin K is obviously not exhaustive. I am not a researcher and I am very aware of it’s simplicity and lack of elegance.  Therefore, I ask for your input not only on the subject, but on how to be better at research, and presentation of ideas.  It would be nice to be able to write about a subject in a way that is palatable and understandable.  That said, here is my vitamin K paper. 

Neonatal Vitamin K Prophylaxis

Annie sewell

NSG 225

24 February 2006

 

The presence of turbulent blood flow through neonatal alternate circulation, which lasts up to two days post partum is a direct contraindication for the administration of prophylactic vitamin K in neonates.

While it is not in the scope of this paper to expound upon the nuances of vitamin K synthesis, blood coagulation, and fetal blood coagulation as it relates to intestinal flora and fat synthesis in the liver, the above topics will be touched on as much as needed to discuss the efficacy of neonatal vitamin K prophylaxis.  

Standardized vitamin K prophylaxis: A history

In the 1930’s, hemorrhagic disease of the newborn (HDN) was the diagnosis given to several neonatal deaths from intracranial hemorrhage (Rothville, K.,2006).  In an effort to eliminate HDN, scientists found that these infants all had low levels of vitamin K and prothrombin, which was the only similarity found among the babies, and so concluded that this was the cause (Rothville, K.,2006).  In 1961, the American Academy of Pediatirics, in response to growing alarm over several infant hemorrhagic deaths, recommended that an IM vitamin K preparation called, phytomenadione, be given to all neonates (Hey, E.,2003).  

The estimated number of deaths from HDN before vitamin K prophylaxis was 411 out of 100,000 live births (Pereira,SHearer, Williams, & Mie-Vergani, 2003), and those statistics have only been reduced to 1.4-6.4 out of 100,000 live births since the implementation of prophylaxis (American Academy of Pediatrics, 2003).  To add to the dubious nature of the standardization of vitamin K prophylaxis, it has been found that half to three quarters of babies who presented with HDN were found to have an underlying liver malabsorption disorder (Hey, E., 2003).

Vitamin K and coagulation

Vitamin K, one of the four fat-soluble vitamins stored in the liver, is responsible for the proper functioning of the clotting factors II, VII, IX and X (Booth, S.L., 2000).  Vitamin K is a co-factor needed to activate surface agents of the vitamin K dependent coagulation proteins, which enables them to stick to membrane surfaces (Bowen, R. 1999).  This ability to adhere to one another and to damaged endothelium is important, as it is through adherence that the chronological reactions of coagulation and clotting take place (Bowen, R., 1999).  It is important to note that the intrinsic pathway of coagulation is activated when the blood “detects an insult” via contact with an unevenness or break of the blood vessel endothelium.  The intrinsic clotting pathway is initiated by non vitamin K dependent factor XII  and platelets (Guyton, A.C., 1987).  Coagulation factors XI, XII, and XIII appear in low levels in fetal blood, while platelets and factors X, VII and fibrinogen are at adult levels (Olds, S., London, M., Ladewig, P., Davidson, M., 2004).  

Because vitamin K is fat soluble, it cannot be activated unless the liver is functioning properly in conjunction with adequate bile and pancreatic enzyme activity to ensure proper absorption and synthesis of vitamin K (Rothvill, K., 1999).  In order for vitamin K to be absorbed from the intestines, natural bacteria and adequate amounts of medium chain fatty acids must be present in the intestines (Rothville, K., 1999).  Breast milk, especially colostrum and hind milk, contain large amounts of vitamin K as well as being a rich source of fatty acids and lipase which aid with early and complete fat digestion in the human gut (Hey, E., 2003).  Fetal intestines are full developed with adequate enzyme activity to metabolize nutrients by 36-38 weeks, therefore early feedings will provide the bacteria needed for proper synthesis and uptake of fat soluble vitamins i.e., vitamin K (Olds, S., et al, 2004).

Fetal Circulation

There are three distinct alterations in fetal blood flow: 1) the ductus venosus which bypasses the liver, (providing only half the amount of extra uterine blood supply to the liver), 2) the foramen ovale which is an opening between the right and left atrium and, 3) the ductus arteriosis which shunts the bulk of the blood flow returning from the pulmonary circulation to the descending aorta (Fetal blood and circulation, 2006).  These alternate pathways, while normal in fetal circulation, have serious consequences for the newborn if they do not close properly.  It must be emphasized, however, that while closure of the three alternate pathways of fetal blood flow is imperative for survival, the normal time frame for closure can be up to several weeks after birth (Verklan, T., 2002). 

Neonatal blood flow and dynamics

During the transition from intrauterine to extra uterine life, neonatal hemodynamics undergoes dramatic, and at times, unstable shifts as the lungs take over respiration (Verklan, T., 2002).  Neonates have a high pulmonary vascular resistance (McConnell, M., Elixson, E., 2002), as well as the possibility of right to left shunt termed, “bidirectional flow”, through the ductus arteriosis (Olds et al., 2004, p 772), and possible prolonged closure times of alternate blood flow pathways as before stated.

Neonatal coagulation and turbulent blood flow

One of three factors must be present for thrombus formation: endothelial injury, turbulent blood flow or hypercoagulable blood, collectively referred to as Virchows Triad (Demark, T., 1999).  As was discussed above, direct insult to blood precedes the activation of the intrinsic pathway of coagulation, which is non vitamin K dependent.  Turbulent blood flow is an insult to blood as proven by Virchow’s Triad.  Neonatal blood is arguably not hyper coagulated, and in the absence of endothelial injury, the neonate is, amazingly, at risk via bidirectional blood flow, (turbulent blood flow), for thrombus formation.

Putting the pieces together

It would seem that the obvious is staring us in the face.  Neonates, at birth, have lower levels of vitamin K, prothrombin and clotting factors XI, XII and XIII, and it is agreed that this is normal.  It is agreed too, that  at birth, neonates have high pulmonary vascular resistance to overcome and bidirectional blood flows that may not resolve for weeks.  At the first feeding, bacterial flora are established aiding the liver and gut in synthesis and uptake of vitamin K, thus activating the full compliment of blood coagulation factors.  There is a two to five day post-birth nadir of prothrombin in neonatal blood (Olds, et al., 2004), and  vitamin K  levels as well as coagulation factors are not fully developed until nine months (Olds, et al., 2004).

Rather than being the cause of unexplained hemorrhage,  low vitamin K and clotting factor levels appear to protect the neonate from thrombus formation during a time of hemodynamic transition.  In no other time of life do we have normal changes in blood flow pathways, and if blood flow pathway changes do occur, they are treated immediately with anticoagulation.  In no other case of turbulent blood flow or high pulmonary blood pressures is coagulation therapy implemented, it simply is not common sense.

Conclusion

The efficacy of neonatal prophylactic vitamin K therapy is controversial at best.  While it is true that neonates have low vitamin K levels and low coagulation levels, these findings are normal, and occur in all neonates.  HDN is a frightening phenomenon and one that cannot be disregarded as fluke.  However, the evidence would suggest that rather than focusing on blood coagulation, the research ought to aim at discovering the similarities in lifestyle, diet, and medication and prenatal care of those babies who do hemorrhage.

Vitamin K therapy has proved successful in treating bleeding disorders in neonates and ought to be considered for infants who have sustained trauma during birth. A thorough maternal history will alert the nurse to any predisposing factors to HDN such as certain medications, and drug or alcohol abuse.  Nurses also ought to be familiar with the signs and symptoms accompanying acute hemorrhage, which does respond rapidly to vitamin K therapy (Hey, E., 2003).  

As part of the nursing standard of care, we are to first, “do no harm”.  The two populations most in need of advocacy are the young and the old, and it is the nurse’s responsibility to provide theat evidnece-based advocacy.

Excellent nursing practice requires that the nurse be aware of current trends and practices and be able to tell the difference between those practices that are based in sound reasoning from those that are not.  It also requires that the nurse speak on behalf of sound practices.

 Questioning the efficacy of neonatal vitamin K prophylaxis seems archaic, since the practice has been so long accepted.  Widely accepted, often unquestioned nature of many medical practices ought to cause the nurse to begin to reevaluate accepted standards of practice with an eye to understanding if they are truly based in sound reasoning.

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Children and Medicine

Posted in Uncategorized on September 12, 2008 by southsanjuan

long before I became a mother, it bothered me a great deal that when it came to children and medicine, things became far more axiomatic.  You will agree, will you not, that one of the more vague, largely anecdotal areas of medicine is vaccinations.  I know, not good to push buttons so early on, but please, hear me out b/c I write to learn, not to tell you how it is.  

I noticed early on that there were many “interventions” performed on new born babys and wondered why.  the answers i received did not help me to fully understand, so i did my own research.  what you read on this blog is my research.  i realize that it may be full of holes, but unless you tell me, i cannot know.  again, please write to me, respond, correct, comment, postulate–i want to learn!

Axiom

Posted in Uncategorized on September 12, 2008 by southsanjuan

Axiom.  When you look up the many definitions to the word axiom, you find words like, “assumed to be true”,  “self-evident” , not necessarily proved, but accepted as true by most, “widely accepted” on it’s own merit, a truth believed to be “self evident”.  You do not find the words law or proved in any of the definitions.  

When I was in high school, my sister and I decided to home school for the last part of high school.  I forget why I did this, my sister was ready to be done with high school and so, did it to graduate early.  I still am not sure why I did  it.  The greatest thing about home schooling, is that you are free to design your own curriculum and courses; you can teach and learn anything you want.  My brother who understood this very well, designed a short course for my sister and I about how to think.  I will never forget what I was taught that day because I have taken it into all of life and applied it to my benefit time and time again without fail.

Our first lesson was simply to define the word, Axiom.  Once defined, Gabe told us not to let anyone tell us that something was axiomatic.  That was it.  The rest was up to us to think about and ponder.  And I did.  And still do.  Because of this, my approach to medicine–nursing and respiratory therapy–have been not only to understand why the body works the way it does, thus understanding why it responds to therapy the way it does, but to make sure that I do not accept medical axioms–which there are many–as self evident truths not to be questioned.  

I am not anti-establishment, nor do I think I’m more intelligent than doctors or those with the experience I could only dream about.  On the contrary, the most important lessons I have had have been from doctors and other medical professionals taking time to help me understand, to answer my questions.  For that I am most grateful b/c without dialogue between professionals at all levels–especially when a question is raised about an accepted practice–there will be no advancement, no true evolution toward better medicine.  

That said, I would ask that any medical professionals, doctors, RN’s, RT’s, researchers, pharmacists, etc, who read my blog and have a thought, idea, opinion etc to PLEASE post.  I want to learn.  I understand that the word axiom works both ways.  Therefore, I understand that b/c I have come to a conclusion, that it too, is not axiomatic–so help me to see, to understand, and maybe I can help you, too.

The bigger idea

Posted in Uncategorized on September 9, 2008 by southsanjuan

I am a nurse by education, by degree.  I was a respiratory therapist before that.  Long  before, I remember sitting in my bedroom literally reading an ancient edition of Greys Anatomy; a book I still have and treasure. 

Longer ago than all of this, I met two of the most intriguing women in my, then, young life.  The impact was long lasting, and I still believe that this  is why, after almost 20 years, I am a nurse.  

I remember the first day in Ukarumpa, Papua New Guinea.  I remember thinking it would be more surreal, but somehow it did not seem so far away.  It felt good–as I remember it now.  Medicine was different in the third world jungle.  Not better, not worse, just different–more practical.  Again, as I remember it.  What I remember most is how I wanted to do that–be that nurse in the jungle.  I did not know it then, but looking back, I realize that my personal beliefs and theories on good medical practice were shaped in Papua New Guinea.  I remember the hospital in Lae.  One large, open-air room with concrete floors, plywood stalls were rooms, muslin curtains for doors.  It worked, it was not perfect–no medical establishment is, I have since found.  Being as young as I was, I was not able to percieve the workings of the clinic, how well it served its population, what sort of medical practices were taking place; what I did percieve is that it seemed to me to be simple and to the point, and I adopted that as my personal medical thesis that day without realizing until much later.

I believe in simplicity and getting to the point now, more than ever before.  With the understanding that experience and education have afforded me, I have never been more sure of my third-grade medical thesis.  As an RT, I was centrally involved in our hospitals emergency room and intensive care unit patient care.  It was during this time that I became certain that emergency medicine embodied the simple, to the point medical practice which I so admired.  I determined to become an ER nurse and travel to third world countries to practice.

Since having graduated from nursing school, I have only been able to practice nursing for one year, and that in a clinic setting, before becoming pregnant and giving birth to a beautiful girl.  I have chosen to stay at home and raise our baby, during which time, I intend to use my time to further study the area of expertise which I have chosen.  

That is what this blog will be about: my studies into the area of emergecny room/critical care nursing.  I have no set plans, other than that this blog will serve as an outlet for what I am learning.  

This blog started out as a fashion blog, but I changed it in light of true need that I’m seeing in this world.  The poor and needy are being killed, the ruthless lovers of self are becoming stronger and it is becoming clear that the line is being drawn and all men will soon be forced to take sides.  That is how it is.  I am choosing my side and that helps me see what matters.