Management of Pain in Children 1

By  Dr. R.M.Mudiyanse

 

Introduction

     Pain is one of the most common symptoms in children. Pain in children can be due to trauma, burns, infections, vascular occlusions, tumors or due to clinical procedures. Perception of pain is subjective. Two individuals may perceive deferent intensities of pain due to the same procedure or illness. Intensity and impact of pain on a person depends on the interaction of physiological, psychological, behavioral and developmental factors. Environment, context and the behavior of relatives and healthcare personal play a major role in modifying the pain experience. Enhanced suffering is involved with pain, when it is out of control, chronic, and when the cause is not known.

 

Pain is a Multidimensional Experience

      Pain is not only a noxious sensory stimuli, it is a multidimensional experience with an affective-motivational, sensory-discriminative, emotional and behavioral components. When the painful stimuli are transmitted to the brain stem and thalamus, multiple cortical areas such as reticular system, somatosensory cortex, and limbic system are activated. The pain is modulated by descending modulatory pain pathways (DMPP) and these can lead to either an increase in the transmission of pain impulses (excitatory) or a decrease in transmission (inhibition). By 26 weeks of gestation, pain pathways and cortical and sub-cortical centers involved in the perception of pain are well developed. Neonates have considerable maturation of peripheral, spinal, and supraspinal afferent pain transmission. They respond to tissue injury with specific behavior and with autonomic, hormonal, and metabolic signs of stress and distress. However, descending inhibitory pathways that help in coping with pain develop later than the afferent excitatory pathways. Therefore, pain sensitivity in neonates may be more profound than that of older individuals in contrast to the notion that neonates feel less pain.  Unfortunately, the existing practice is to give only minimal analgesia or anesthesia for neonates.

 

Pain Not Only Hurts But Also Causes Harm

      Short-term adverse effects of inadequate pain relief include biochemical, physiological and behavioral changes. Increased anxiety, somatic symptoms, sleep disturbance, agitation and crying will leads to distress in parents. Biochemical changes induced by pain include hyperglycemia, increased protein metabolism and increased oxygen consumption. Physiological changes such as increased heart rate and blood pressure, and decreased gut mortality and transcutaneous oxygen saturation will also contribute to adverse out comes.

      Inadequate pain relief has long term implications. Inadequately managed prolonged and repetitive pain results in development of altered coping mechanism in the brain resulting in increased anxiety and hyper responsiveness to painful stimuli (hyperalgesia) and non-painful stimuli (allodynia) in later life. Children offered inadequate pain relief tend to have prolonged hospital stays, higher mortality, exaggerated response to pain and long term behavioral, psychological sequelae and learning difficulties. Infants who were circumcised without anesthesia as neonates showed increased distress during routine immunizations at four to six months of age, as compared with uncircumcised infants or with those who were circumcised as neonates with the use of a topical local anesthetic. Among children with newly diagnosed cancer, those who had inadequate analgesia during the first bone marrow aspiration or lumbar puncture showed more severe distress during subsequent procedures than those who received oral transmucosal fentanyl citrate during the first procedure.

 

Pain in Children is Under Estimated and Inadequately Treated

      Despite well recognized acute and chronic adverse effects of pain on a child, pain in children and neonates is often inadequately assessed and inadequately treated. According to a recent review, 80% of patients including adults and children are not getting adequate pain relief even though pain relief is possible in 90% of patients. Situation is worse when it comes to children. Children are given less pain relief than adults when they undergo the same procedures. In 1970s, neonates were subjected to surgery with minimal anesthesia assuming that they do not feel pain. In our hospitals in Sri Lanka even at present pain-full minor procedures like lumber puncture, IV cannulation, wound dressing, suturing and even circumcision are performed with inadequate anesthesia or analgesia. Restraining a child for a procedure is not an uncommon scene in our children wards.

      Several factors contribute to the ignorance of pain management in children. Misconceptions, inadequate knowledge, non-availability of drugs, ignorance about pain assessment tools and deficiencies in pain management policies of institutions are among those factors.

     There are numerous misconceptions about pain in children. Some believe that children do not feel pain or despite the fact that they feel pain they think that they do not remember it. Sometimes, long-term and short-term sequelae of pain are not appreciated by medical professionals and parents. Some adults seem to believe that pain can build the character of a child by inculcating champion’s traits such as courage, self-discipline, independence, and self-sacrifice. However, research has demonstrated that pain has more negative effects on the character of a person. Doctors who rely too much on pain as a tool for monitoring tend to avoid pain relief. However, research has shown that pain relief given to patients with abdominal pain has not interfered with diagnosis or management. Another reason for inadequate pain relief is the belief that pain helps healing through immobilization of affected parts. However, it is not impossible to achieve immobilization by other means even after relieving pain. Inadequacies of knowledge about pain management and the fear of adverse effects of analgesics have made the situation worse. Drug doses, their metabolism and interactions are different and complex in neonates and children.  This partly explains the doctor’s reluctance to prescribe pain relief. Inherent difficulties in assessment of pain, non-availability of assessment tools result in inconsistent assessment and treatment. Some doctors tend to believe that assessment of pain takes too much of their valuable time and they are inclined to offer pain relief without assessment, which results in inconsistent and unreliable pain management. Considering the ethics of medicine, healthcare professionals are committed to “do no harm” rather than “do not hurt”. If a doctor over estimate possible adverse effects of drugs used for pain relief he might consider tolerating and accepting pain. However, harmful nature of pain is well established. It has been established beyond doubts that the advantages of pain relief exceed possible adverse effects of drugs when they are used in correct dose regimens. Therefore, not using all the available means of relieving pain is not justifiable.

 

Assessment of Pain in Children

     Proper management of pain starts with proper assessment of pain. Pain assessment in children is complicated due to many reasons. Pain is a subjective feeling necessitating the need to rely on the report by the individual. Self-report of pain depends on the individual personality, development and communication ability of a child. Pain expression by a child reflects the physical and emotional state, coping style, and family and cultural expectations. Sometimes self-report does not reflect the intensity of pain therefore needs to be supplemented by observations and physical signs that may reflect pain. Observations made by healthcare professionals are also subjective; they depend on training and attitudes. Therefore, intensity of pain assessed by health care personal on observations also requires careful interpretation. Pain is a multidimensional and highly complex experience. Evaluation of pain by its intensity alone is an over simplification. It is like trying to describe music by its loudness. Therefore attention should be given to the impact of pain on child’s activities, emotion and behavior. Child who is depressed may not say that he is in pain; neither will show any signs or expressions to suggest that he is in pain. But he may be not taking his meals or not doing his usual routines as he used to do. In spite of all the complexities and difficulties, pain assessment is an essential routine of good quality health care. Acknowledging pain makes pain visible. Pain assessment should be incorporated into routine observations or as another vital sign, ‘TPRP’, – temperature, pulse, respiration and pain. Several pain assessment scales for self-report have been developed for children above 3 years.

 

Pain assessment tools for self-report

A. Adjective scales (verbal scale)

     Adjective scales involve selecting a word out of a set of descriptors of pain intensity. These scales require verbal fluency at a high school level and have not been investigated extensively with children.

B. Numerical rating scales (NRS)

     Numerical rating scale (NRS) does not require any tools and used for children above 8 years who are familiar with numbers.  It has numbers 0 up to 10 representing no pain to maximum pain respectively. Young children who are capable of counting may provide idiosyncratic and unreliable numbers because they do not understand qualitative significance of numbers. The tool has not being validated in research.

C. Visual analogue scale (VAS)

     Visual analogue scale (VAS) is used for children above 7 years. VAS can be a plain line or a multicolored line usually of 100mm in length (more information under assessment of pain). Child requires to selecting a point on the line representing the pain intensity. The length up to the point indicated by child will give a quantitative assessment of the pain intensity. Developing mechanical sliding scales has eliminated the need for measuring but they involve a cost and risk of cross infection. VAS have demonstrated good sensitivity and validity for most children at age seven years and older by research.

D. Faces scales

     Faces scales require selecting a picture (drawing or a photograph) of a face that represents one’s pain intensity. This tool can be used for younger children up to 3 years and does not require numeracy or ability to estimate. Drawings are easily reproduced and represent both genders and broader demographic groups than photographs. Face scale has the advantage of not been remembered by the patients as numbers and words used in other scales. Therefore each time the child will give consideration to the intensity of pain before reporting it.

E. Pieces of Hurt

     The Pieces of Hurt tool (also known as Poker Chip Tool) quantifies pain intensity by using four poker chips to represent amounts of pain. The Pieces of Hurt tool has been used as a comparison tool to support the criterion validity of other pain tools, such as the pain ladder and the VAS.

 

 

 

 

 

 

 

F. Color scales

     The color scales is not same as colored visual analogue scale. Here the child selects crayons and draw colors matching different levels of pain severity. This tool has not being researched adequately and it takes longer time to administer. And now rarely used in clinical practice. The color scale also has the advantage of not been remembered by the patients.

 

When the child is not capable of communicating

     Pain assessment is difficult in children with communication difficulties due to neurodevelopment disorders or when they are sedated or ventilated. In such situations pain assessment will depend on behavioral observations and physiological changes.  FLACC (Faces, Legs, Activity, Cry and Consolability) is a simple and consistent method for nurses to identify, document, and evaluate pain in children who have difficulty in verbalizing the presence or intensity of pain. Other behavioral pain scales that has been developed especially for critically ill sedated and mechanically ventilated adult patients also can be used for children. These scales rate a patient's facial expression, upper limb movement, and compliance with mechanical ventilation.

 

The parents’ role

     Parents’ contribution in management and assessment of pain is very useful. They know their child better. Parents should be encouraged to assess and report about pain in children. Parents can usually tell the difference between cries from hunger or a wet diaper versus cries due to more serious distress. Children aged 3-4 years tend to become quiet and inactive while in pain or they may become extremely agitated. Parents can understand this better. Sometimes children of this age use unusual words to describe pain that parents can understand better than health care professionals. Parents can help using pain assessment tools in school aged children. School aged children are capable of providing more specific information such as site of pain and character of pain. And listening to the child who is in pain is more informative than any assessment tool.