Pain Management in Cardiac Surgery - Essay Example

?Pain Management in Cardiac Surgery Over the last years of medical advancement, significant improvements in assessment and management of surgical pain had been made. There has been an escalation in effectiveness of pain management as well as quality supporting literatures available. Nevertheless, efficiency of its application in patient care still needs to be continuously evaluated and monitored. Thus, review of relevant studies and previous researches are presented in this paper to create a collaborated idea of pain management in post-cardiac surgery patients, its application in nursing care, and suggested strategies to improve future nursing care practice. Overview of Pain and its Management Pain is a subjective and relatively complex perception that indicates presence or occurrence of tissue damage in the human body. It is the body’s natural response to infection or injury to signal the person that something is damaged in the system (Definition and Types of Pain, 2012). Nociception is the process involved in pain perception where stimuli from potential tissue damage are transmitted through peripheral and central nervous systems (Portenoy and Brennan, 1994). Stimulus begins in the detection of either mechanical, thermal or chemical changes in the pain receptors, also known as nociceptors, which is activated when the source is above the threshold of the person. The stimulus will then be transmitted along the spinal cord to the brain and in turn will trigger autonomic reaction of a subjective painful sensation (Clement, et al., 2000). Pain is necessary in recognition and diagnosis of health problems that may be acute or chronic. Acute and chronic pain differs in the onset and duration of painful sensation. Acute pain such as after surgery, trauma, and labour usually lasts for hours, days or weeks up to less than six months time. After the underlying cause is treated, the pain subsides along with the healing process of the illness. On the other hand, chronic pain are those experienced by the patients for months or even years where pain management has been less effective overtime (Definition and Types of Pain, 2012). There are three types of pain according to mechanism: nociceptive, neuropathic, and psychogenic. The first type, noriceptive pain, is primarily generated by pain receptors as previously discussed. Neuropathic pain involves potential damage in neurons or any part of the nervous system such as in cases of diabetic neuropathy and post-stroke pain. While psychogenic pain is associated with psychological disturbance occurring in anxious or depressed patients particularly those with chronic or terminal illnesses (Definition and Types of Pain, 2012). In this study, the acute type and noriceptive type of pain will be tackled as surgical pain falls into these categories. Neuropathic pain is further categorized into somatic and visceral where somatic pain is usually caused by integumentary, skeletal, and muscular injuries. Pain can be described as dull or aching in a localized area of the body. In cases that injury occurs in the skin or on tissues beneath, a sharper sensation of pain is usually experienced since nerve endings and pain receptors are rich in the integumentary system. The latter type, visceral pain, is initiated by injury of internal organs and are experienced as dull, stabbing or cramping sensation that is poorly localized (Janig, 1987). Surgical wounds can develop either or both depending on the part affected and the procedure done. Pain following a surgical procedure is expected especially in the invasive procedures where tissues and organs are damaged and repaired. Since it is primarily subjective, proper assessment must be well utilized. For adult patient or those above eighteen years old, interview and physical assessment are the critical part of assessment. Since they are able to verbalize their feelings, specifications of pain can be fully described. The essential components of the interview are asking the patient of the following: (1) characteristic – whether the type of pain is stabbing, sharp, or dull, (2) location – both the origin and the area/s of radiation, (3) duration and interval, (4) severity – patient will be asked to rate the pain on a scale from 1 to 10, with 10 as the worst pain ever experienced, (5) movement of pain location if there is any, and (6) things or movements that make pain better or worse. Furthermore, objective data must also be gathered to further support a reliable assessment. Symptoms to observe may include temperature that is higher than 100°F, nausea, vomiting, constipation or diarrhoea, presence of pus or discharge from the wound, redness or swelling of the affected area, and shortness of breath (Ameres, 2005). For paediatric patients who are not yet well versed in expressing their thoughts and feelings, tools of imagery are utilized to facilitate identification of pain scale and the presence of pain as such. McCarthy, et al. (2005) suggests in his study entitled “Visual analogue scales for assessing surgical pain” the usage of visual analogue scales called Surgical Pain Scales or SPS as a tool to assess affective and sensory components of postoperative pain. They claim that SPS is designed to measure pain in several levels of activities such as while at rest, during normal activity, during exercise or work, and the malevolent sensation of pain. It was also concluded in their study that SPS is an excellent tool to track progress of pain and effectiveness of pain management both in paediatric and adult patients. Unfortunately, locating the primary source or radiation of pain in paediatric patients may post some challenge. Interviewing their primary caregiver and asking their help to identify with any behavioural changes such as irritability can aid in proper assessment of pain in the young. Physicians and nurses must advise the parents to watch out for nonverbal signs of pain such as intractable crying, irritability, poor feeding or eating, poor drinking, or even lethargy (Ameres, 2005). Although there are not enough studies that suggest any significant difference on pain perception between the older and younger age group, a study by Gagliese, et al. (2005) reflected that older patients self-administered lesser morphine than the younger patients postoperatively. This may signify that older people are more tolerable to pain than the younger population. Nonetheless, the older population still requires equivalent attention perioperatively as their age group has higher incidence of postoperative morbidity and mortality such as pneumonia and cardiovascular disorders (Marusch, et al., 2005). Gender plays a role in pain management as reported in the study of Morin, et al. (2000) in their study “Differences between the sexes in post-surgical pain”. Their study shows that women have lower pain threshold and lower tolerance to post-surgical pain. While another study rendered by Frot, et al. (2004), stated that men have lower tolerance for sustained low-level pain and have higher anxiety related to pain than women. Nevertheless, due to the subjectivity of pain, a patient’s complaint of its experience must be taken into consideration and not be left unnoticed (Frot, et al., 2004). In addition, healthcare providers must be sensitive not only to the verbal statement of the patient related to pain but also to non-verbal cues such as facial expression as Riva, et al., (2011) stated that women’s facial expression are often times not easily recognized by observers. Cardiac Surgery Cardiac surgery, cardiovascular or cardiothoracic, are procedures performed by highly specialized cardiac surgeons to correct congenital defects, treat valvular heart disease, and other complications of myocardial ischemia. Some of the cardiac surgeries performed today are (Doty and Doty, 2012): Modified Fontan procedure for single ventricle damage Palliative operations for congenital thoracic arteries and veins disorder Aortic valve replacement, mitral valve and tricuspid valve reconstruction for acquired valve lesions Coronary artery bypass graft for ischemic heart disease Bypass of superior vena cava for acquired thoracic arterial and vein injury Special operations such as cardiac transplantation, lung transplantation, or heart-lung transplantation Due to its invasive nature, cardiac surgeries posts high risk of developing postoperative complications primarily the initiation of acute surgical pain, bleeding, infection, and pneumonia to name a few. These risks are reduced by creation and usage of robotics in the operating theatre where smaller incisions are made, therefore creating lesser postoperative pain and bleeding (Franco and Verrier, 2003). Specifications and techniques of the aforementioned cardiac surgical procedures will not be discussed in this paper. The researcher will focus on preoperative evaluation, assessment of surgical pain, complications of cardiac surgery, and pain management. Preoperative Evaluation Ensuring an optimal outcome in vital for cardiac surgeons and to attain this goal, adequate preoperative evaluation must be made prior to the decided surgical procedure. With innovations in technology and technique, cardiac surgeries transited to elective surgeries where on the day admission is practiced. In similar scenarios, both cardiologist and cardiac surgeon must ensure thorough assessment of the patient to eliminate morbid postoperative complications, be able to predict the surgical outcome, and plan for individualised treatment strategies. This includes “medical history evaluation, physical examination, laboratory and diagnostic tests, anaesthesia evaluation, risk assessment, and patient education regarding the planned operation” (Lemmer and Vlahakes, 2010). Since there is quite a sum of cardiac diagnostic tests available, the cardiologist’s discrepancy is critical in selection. Some of the available diagnostic procedures are: stress test, myocardial perfusion imaging, stress echocardiography, cardiac catheterization, echocardiography, myocardial viability imaging, CT angiography, aortography, magnetic resonance imaging (MRI), magnetic resonance angiography, and pulmonary function test. Among these varieties, cardiac catheterization or coronary angiography is considered the gold standard in preoperative evaluation on most types of heart disorders (Lemmer and Vlahakes, 2010). Unfortunately, none of the cited diagnostic procedures measures the risks involved regarding probable surgical pain. Nursing theories suggests that preoperative assessment of patient’s readiness promotes better postoperative outcome. This supports the ideal practice of counselling or discussing with the patient the contemplated procedure encompassing what to expect before, during, and after the surgery (Bojar, 2011). A study by Kalkman, et al. (2003) stated that severe postoperative pain can be predicted during preoperative assessment or visit using identified predictors. Together, they developed a prediction rule that can be utilized for surgical inpatients postoperatively to assess early severe pain. The study suggests identification of the following predictors: “Age, gender, type of scheduled surgery, expected incision size, blood pressure, heart rate, Quetelet index, the presence and severity of preoperative pain, health-related quality of life the (SF-36), Spielberger's State-Trait Anxiety Inventory (STAI) and the Amsterdam Preoperative Anxiety and Information Scale (APAIS) (Kalkman, et al., 2003).” Although the study has shown effectiveness of this scoring rule, it has yet been validated neither on other clinical setting nor on cardiac surgery patients. Other research suggests the utilization of Pain Matcher in predicting the intensity of postoperative pain. They experimented on usage of electrical stimulation to be introduced to patients preoperatively to assess their pain threshold and tolerance and claim that this assessment can predict possible postoperative pain (Nielsen, 2007). Pain Scales for Assessment There are several tools available for pain assessment. The researcher selected the most common utilized scales (Gillian, et al. 2011) to initiate comparison and later end in conclusion on which scale is more accurate and appropriate. 1. Numeric Rating Scale (NRS) Fig. 1. Numeric Rating Scale (McCaferry and Beebe, 1993). This pain assessment tool can be conducted to adults and children above nine years old. The patient is asked to rate the perceived pain in a scale of 0 to 10 with zero as no pain, 1-3 as mild pain, 4-6 as moderate pain, and 7-10 as severe pain (McCaferry and Beebe, 1993). The health care provider in collaboration with the medical team will then be able to understand the level of surgical pain and manage it accordingly. Kerbs, et al. (2007) evaluated the diagnostic accuracy of NRS and concluded in their study entitled, “Accuracy of the Pain Numeric Rating Scale as a Screening Test in Primary Care,” that it is indeed a reliable tool as it being the most utilized in pain assessment. 2. Verbal Descriptor Scale (VDS) Fig. 2. Verbal Descriptor Scale (Iowa Geriatric Education Center, 2009). This tool can be used for more articulate patients such as the adult and elderly. The patient will be asked to choose from the selections in congruence to the current perceived surgical pain. The nurse will record the score by rating “No Pain” as zero and “The most intense pain imaginable” as six. Monitoring of the progress of pain or effectiveness of pain management may be done through computing the mean score of all the assessment times or by keeping track of the values which may be well presented by a graph (Herr and Garand, 2001). Edelen and Saliba (2010) made a comparative study between NRS and VDS and concluded that both is as effective and accurate as the other depending on its suitability to patient’s ability and selection of which scale will be utilized will solely base on the practitioner or physician’s discrepancy. 3. Visual Analog Scale (VAS) Fig. 3. Visual Analog Scale (Wewers and Lowe, 1990). Figure 3 shows an example of horizontal VAS that can be conducted to an adult patient. It represents a continuum of “No pain” and “Pain as bad as it could possibly be”, in other words, none to worst. This aims to measure pain with the patient’s perspective that this scale is continuous. If this will be employed, the baseline must be ten millimetres long and after the patient places a dot or points as to where the pain is, the practitioner will measure it by millimetre starting from left to right. The progress of pain will be determined by the inclining trend of the measure, while effectiveness of pain management will be reflected when the trend declines (Crichton, 2001). Fig. 4. Wong-Baker Faces Pain Scale (Miller and Jolley, 2001). Figure 4 illustrates another type of VAS where faces are drawn as presentations of the pain level. This tool is designed for paediatric patients and those with cognition disorders. The practitioner will select the illustration that best represents the patient’s facial expression or reaction in response to surgical pain. The smiling face parallels “no pain” and crying face to “worst possible, unbearable, excruciating pain” (Newman, et al. 2005). Bijur, et al. (2001) supports the reliability of VAS in pain assessment stating that “ninety percent of the pain ratings were reproducible within 9 mm”. On the other hand, Bodian, et al. (2001) insists of categorizing the measurements of VAS when used in research for better clinical bearing. 4. McGill Pain Questionnaire (MPQ) It is a comprehensive assessment of significant pain where both the intensity and quality of pain may be described. The standard version noted 45 specific descriptions of pain to be chosen by the patient according to the quality of pain they currently perceive. Each description has a corresponding score that the practitioner will sum. It also includes pain changes, practices to alleviate pain, and a five-point scale questionnaire to determine the intensity of pain (Melzack, 1975). Although comprehensive, the downfall of MPQ is its length and the time it consumes for complete conduction. Melzack (1987) formulated a shorter form of MLQ which, as he acclaims, is a reliable tool if there is limited time for a standard MPQ. Gagliese, et al. (2005) suggests in their study that NRS is the most preferred rating scale followed by VDS. They further discussed that older patients find some difficulty in answering VAS and concluded that this type of rating scale is not appropriate for their age group. In summary, the selection of pain assessment tool to be used lies on the practitioner’s judgement and the patient’s capabilities (Edelen and Saliba, 2010). Postoperative complications. Most of the patients who undergo less invasive cardiac surgeries such as angioplasty resume their routine activities after few days or weeks (Katz and Seltzer, 2009). With the advent of better and up-to-date surgical, anaesthetic and monitoring techniques, perioperative problems have been generally reduced nowadays. Surgical pain that lasts longer than the usual are red flags for physicians as this may indicate post-surgical complications such as infection, dehiscence, hematoma, vomiting, constipation or ileus, lung complications, formation of fistula, and bleeding. In such cases, palliative management must be adjunct with treatment of the underlying cause (Ameres, 2005). Special attention to elderly patients must be observed as they are the more common to receive invasive cardiac surgeries. A study entitled, “Age related risk and prevention of postoperative complications,” concluded that: Complications in the postoperative show different frequencies and mainly depend: a) on age-related conditions of pulmonary, cardiovascular and renal functions, of C.N.S. and of nutritional status; b) on surgery and medication-related risk factors, inclusive of emergency, bed rest, analgesia and infusions, drugs and intensive care; c) on neoplastic or non-neoplastic disease, type of surgery and surgeon's experience (Beltrami, 1998). Simple clean or sterile surgeries are oftentimes have a shorter period of surgical pain although there are cases where completion of wound healing takes longer than usual due to underlying factors such as patient’s general health condition prior to procedure, presence of coexisting medical problems such as kidney diseases or diabetes mellitus, and cigarette smoking as it contributes to narrowing of blood vessels resulting to poor blood perfusion in areas of injury which is necessary to hasten the healing process (Ameres, 2005). Basic rule in surgery implies that minor procedures involve smaller risk while major procedures offer otherwise (Jones, 2010). In a minor cardiac surgery, the usual complications expected are nausea, vomiting, minor bleeding or hematoma, minor infections, pain and sometimes neuropathy. Conversely, major cardiac procedures can have critical complications such as cardiovascular attack, myocardial ischemia or infarct, graft failure, hypovolemia secondary to massive bleeding, cardiopulmonary problems or even failure, kidney failure, nerve or organ damage, and death (Little and Merrill, 2011). It is said that ten to fifty percent of individuals who undergo cardiac surgeries such as coronary artery bypass experiences acute postoperative pain followed by persistent pain where two to ten percent of them suffers severely. Studies point to iatrogenic neuropathic pain as the main cause of chronic surgical pain (Kehlet, et al., 2006). Neuropathic pain is prompted by damage made to the somatosensory nervous system during surgery, genetic polymorphism, and aging. The damage created in the nervous system fires up spontaneous pain stimuli creating chronic pain on the part of the patient (Costigan, 2009). Historical cohort study conducted by Bruce, et al. (2003) concluded that chronic chest and leg pains follow cardiac surgery particularly the coronary artery bypass. They suggest inclusion of this possibility in pre-operative health teaching. Pain Management in Post-cardiac Surgery Patients Surgery parallels to occurrence of pain and just like in any other surgical procedures, post-cardiac surgery patients are in dire need of quality pain management. Scholars argue that although reliable assessment tool and high quality analgesics are administered, there is still poor control of pain primarily due to lack of monitoring and reassessment following analgesia administration (Bucknall, et al. 2007). Patient who underwent major cardiac surgery experiences moderate pain that lasts for few days postoperatively (Gelinas, 2007). Post-cardiac surgery pain may imply optimal recovery (Lynch, 2010) in a way that patients oftentimes report presence of pain during activities essential for recovery such as deep breathing exercises, coughing, turning, getting out of the bed, and ambulating. This poses a critical role for nurses both in pain management and in patient’s fast recovery. Efficient pain management demands for comprehensive assessment, effective treatment, and reassessment or evaluation by collaborative team of health care providers. Recognition of pain, its characteristic and intensity, utilizing the presented pain scales is a crucial part of pain management because it is in this level that nurse and the medical team will base their planning and intervention for the desired outcome or pain relief. Understanding perioperative pathophysiology and implementation of care regimes to reduce the stress of cardiac surgery will continue to accelerate rehabilitation associated with decreased hospitalization and increased satisfaction and safety after discharge. Reorganization of the perioperative team (anaesthesiologists, surgeons, nurses and physical therapists) will be essential to achieve successful fast-track cardiac surgical programmes (Roediger, et al. 2006). Since it was earlier discussed that preoperative assessment is essential to evaluate the patient’s readiness for the surgical procedure, nurses must be advocates of the patient’s preparedness and mind set to pain. During preoperative consultation or counselling, areas of discussion must include patient’s anxiety level, knowledge on the procedure, and post-operative health teachings for faster recovery including helping them attain optimal awareness on the probability of occurrence of pain after surgery. This preparedness will not only reduce anxiety but also lessen the postsurgical pain (Khan, et al. 2012). Most postoperative cardiac surgeries are well managed through controlled administration of analgesics. Form of administration depends on the extent of surgery and the severity of pain, as will be ordered by the attending physician, which could be orally, intramuscularly, or intravenously. The most common analgesics given are opiods and non-steroidal inflammatory drug (NSAID) (Rosenquist and Rosenburg, 2003). In earlier years, a study conducted in surgical wards in Canada shows the ineffectiveness of prescribing low dose, high frequency analgesia beyond the first four days after surgery. It was observed that patients receiving recommended dosage and frequency on the first four days have better outcome in pain management (Melzack, et al., 1987) thus improving the analgesic prescription of the current era. Lavand'homme (2006) concluded that “effective perioperative block of nociceptive inputs from the wound as well as use of antihyperalgesic and analgesic drugs in combination seem the best way to control postoperative pain and specifically to prevent central sensitization”. Intravenous opiods are the drug of choice for patients who had coronary arterial bypass grafting and these can be administered by nurse or patient-controlled methods or the so called PCA (patient-controlled analgesia). The nurses must always assess for any sign of bleeding and renal hypoperfusion and if so, NSAID must be withheld temporarily until bleeding is controlled (Roediger, et al. 2006). Non-pharmacologic pain management may include transcutaneous electrical nerve stimulation (TENS) as per physician’s dictum. To avoid delay in delivery of analgesia, it could be suggested that nurse-driven protocol be implemented on medium care units. This idea is supported with a study by Van Valen, et al. (2012) where they evaluated the effectiveness of nurse-driven protocol in pain management. This concept comprise of the nurses’ independence in administering analgesia even without physician’s order. Proper training and preparation on the part of the nurse practitioner must be acquired prior to full implementation of such protocol. Nurses must be well equipped with knowledge regarding the analgesics – its mechanism of action, safe dosages, mode of administration, contraindications, and adverse effects. Especially for opiods which have a very thin parameter for safe dosage. Prevention of drug addiction and drug dependence must also be observed and prevented by nurse practitioners particularly for those patients receiving PCA (Mcintyre and Schug, 2007). Patient must be educated and continuously reminded on the adverse effects of improper drug administration and drug toxicity. In instances that the pain cannot be relieved by pharmacological intervention, non-pharmacological interventions may be facilitated. There has been a lot of alternative stress reliever, pain reliever, and relaxation techniques available and under research over the past decade. Sedative music and scheduled rest have been proven to reduce anxiety and perception of pain in postoperative cardiac surgery patients (Voss, et al. 2004). Conclusion Pain is a subjective unpleasant sensation that the body utilize to signify tissue or organ damage. Postoperative pain is common and expected especially for major surgical procedures such as in cardiovascular or cardiothoracic surgeries. There are several factors that may affect the patient’s perception of pain: (1) age – where the older adult are more tolerant of pain requiring lesser self-administered analgesia, and (2) gender – where women were said to have lesser pain threshold and tolerance. These factors also affect the practitioner’s recognition and assessment of pain where the younger ones, usually less than eight years old, have lesser ability to express themselves compare to the older adult and that women’s facial expressions are less readable than the men’s. Different tools for pain assessment were also discussed and weighed. In the end, it was decided that all are reliable tools for assessment if utilized properly and according to the patient’s level of understanding and ability to express. These pain scales are recommended to be used during assessment and reassessment after administration of analgesia. Vital signs, physical examination, and non-verbal cues must also be considered by nurse in facilitating thorough assessment. The most common types of cardiac surgery were reviewed including the possible signs and symptoms to watch out for that may indicate presence of postoperative complications. 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