When the head is higher than the heart, more pressure is required to pump blood up to the brain. When changing positions, an individual’s heart must contract more forcefully, blood vessels in the legs need to contract to push more blood to the head, and blood vessels in the head and neck need to open to allow the increase in blood. The autonomic nervous system (ANS) controls blood pressure, and position changes physiologic responses. A symptom of ANS dysfunction is orthostatic hypotension.
This activity within the body temporarily increases blood pressure just a bit. However, when these physiological changes do not occur, blood pressure drops as more blood remains in the lower body. The act of moving the body to an upright position without blood pressure adjustment can make your child feel lightheaded, dizzy, or even pass out or faint. Lowering the head will restore blood pressure and thereby resolve the negative issues.
Individuals of any age who may have OH are those who are dehydrated, overheated, especially from outdoor activity, have low blood sugar, stand too quickly, have had long periods of bed rest, rapid weight loss, have side effects from medications, or are older. Some medical issues that can cause OH include cardiac dysfunction and issues with the autonomic nervous system from brain injury, spinal cord injury or other neurological diseases and trauma. In children, OH can also develop during periods of growth spurts, more often seen in teens during puberty. Children with neurological issues and growth spurts can have bouts of OH periodically throughout their growing years.
Other issues can be confused with OH. These include vasovagal syncope and postural tachycardia syndrome, both of which involve fainting.
Vasovagal syncope is a process where individuals faint due to specific triggers. In this situation, heart rate and blood pressure drop suddenly. It usually is not particular to a disruption of the ANS, but the ANS is affected by a mind-body trigger. Some common triggers are the sight of blood, an injection or blood draw, strain, and stress. A common physical trigger of vasovagal syncope can occur with stimulation during a bowel program. Other physical triggers include lengthy periods of standing, or heat exposure. This does not relate to changing the body position to upright but is often misunderstood at OH. If there is an issue with the bowel program procedure, an anesthetic can be provided rectally to reduce the vagal nerve stimulation. Otherwise, avoidance of the trigger by looking away or distracting and adapting to physical needs is recommended.
Postural orthostatic tachycardia syndrome (POTS) is the occurrence of lightheadedness or fainting when standing after lying down. POTS also can occur just by lifting the arms above the head. It is differentiated from OH as POTS is the rapid pulse on standing or elevating the head, whereas OH is a sudden drop in blood pressure. It usually occurs in women between the ages of 15 and 50. Most outgrow the condition, which is caused by a disruption in the ANS. It is more easily corrected with dietary and exercise adjustments. Compression garments also help with blood flow.
Symptoms of OH in children with neurological issues include blurred vision, dizziness, fainting, nausea, fatigue, difficulty concentrating, and changes in breathing. Children who are developmentally able to communicate may indicate feeling lightheaded or dizziness, allowing the caregiver to lower the child’s head to a resting position. However, younger children or children without speech may not be able to communicate, so observation needs to occur. Blood pressure monitoring and heart rate should be used to determine OH. Therefore, knowing your child’s typical blood pressure range is necessary.
Treatments for OH vary in intensity and by the acuity of the situation. Some children may have OH early on in their course with resolution over time with treatments. However, other children may have episodes periodically as they grow, especially with growth spurts that change their internal adaption physiology.
Treatments include:
Some medications can help with severe OH. These medications should not be taken lightly as they do have possible consequences. Attempting the treatments listed above should be your first action. The medications may be limited to the older child and may not be appropriate for younger children. Medications for OH include midodrine and droxidopa. Both can have significant side effects, especially with urine retention and bladder issues. Both require staying upright for at least four hours after administration to avoid high blood pressure. Other medications have been used for OH, such as fludrocortisone and pyridostigmine, but these have significant side effects.
Non-medication treatments do work overtime. Every child is different. Some move right through OH. Others take a bit more time. There is no specification as to how long regulating the body to an upright position will take.
Quick growth in the years of puberty is a particular time for OH to reappear. As children go through growth spurts, they may or may not go through further OH episodes. These episodes are typically not as significant as the first round right after injury or illness. Symptoms of OH may be more subtle. You may not even see another episode of OH. For some children with progressing disease, OH may develop later. If you are aware of the situation and know what to do, you will be well prepared to deal with this transient issue. Nurse Linda
References and Further Reading:
Stewart JM, Boris JR, Chelimsky G, Fischer PR, Fortunato JE, Grubb BP, Heyer GL, Jarjour IT, Medow MS, Numan MT, Pianosi PT, Singer W, Tarbell S, Chelimsky TC; Pediatric Writing Group of the American Autonomic Society. Pediatric Disorders of Orthostatic Intolerance. Pediatrics. 2018 Jan;141(1):e20171673. doi: 10.1542/peds.2017-1673. Epub 2017 Dec 8. PMID: 29222399; PMCID: PMC5744271.
Vitale MG, Moore DW, Matsumoto H, Emerson RG, Booker WA, Gomez JA, Gallo EJ, Hyman JE, Roye DP Jr. Risk factors for spinal cord injury during surgery for spinal deformity. J Bone Joint Surg Am. 2010 Jan;92(1):64-71. doi: 10.2106/JBJS.H.01839. PMID: 20048097.
Zebracki K, Hwang M, Patt PL, Vogel LC. Autonomic cardiovascular dysfunction and vitamin D deficiency in pediatric spinal cord injury. J Pediatr Rehabil Med. 2013;6(1):45-52. doi: 10.3233/PRM-130236. PMID: 23481891.
Linda Schultz is a leader, teacher, and provider of rehabilitation nursing for over 30 years. In fact, Nurse Linda worked closely with Christopher Reeve on his recovery and has been advocating for the Reeve Foundation ever since.
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