Preoperative Evaluation and Preparation of the Patient

Chapter 19


Preoperative Evaluation and Preparation of the Patient



A crucial element of the perioperative care of the patient includes a timely and thorough preoperative assessment. A fine-tuned approach to patient evaluation then enables appropriate interventions when required to properly prepare the patient for the upcoming anesthesia and surgery. For any patient scheduled to undergo anesthesia, preoperative evaluation is compulsory to help identify factors that increase the risk associated with anesthesia and the status of the patient relative to the proposed surgery. Essential goals of preoperative assessment and preparation of the patient include the following:



• Optimize patient care, satisfaction, comfort, and convenience.


• Minimize perioperative morbidity and mortality by accurately assessing factors that influence the risk of anesthesia or might alter the planned anesthetic technique.


• Minimize surgical delays or preventable cancellations on the day of surgery.


• Determine appropriate postoperative disposition of the patient (i.e., given the patient’s status, whether the procedure is best performed on an ambulatory, inpatient, or intensive care basis).


• Evaluate the patient’s overall health status, determining which if any preoperative investigations and specialty consultations are required.


• Formulate a plan for the most appropriate perianesthetic care and postoperative supportive patient care.


• Communicate patient management issues effectively among care providers.


• Educate patient regarding surgery, anesthesia, and expected intra- and postoperative care, including postoperative pain treatments, to reduce patient anxiety and increase patient satisfaction.


• Ensure time-efficient and cost-effective patient evaluation.


During the preoperative visit, patient assessment begins with a thorough review of the patient’s medical records and patient interview, followed by the physical examination. A comprehensive medical history and physical examination are the cornerstones of a systematic approach to continued patient preparation. Information gathered from this evaluative process guides further individualized assessment (e.g., obtaining diagnostic tests, specialist consultation). The extent of this preoperative workup depends on the existing medical condition of the patient, the proposed surgical procedure, and the type of anesthesia. Significant findings from this initial evaluation enable the anesthesia provider to make adjustments in the patient’s care (i.e., initiate specific treatment modalities to optimize the patient’s condition for the proposed surgery and anesthesia).


Important strategies for achieving high-quality, cost-effective patient evaluation include the following1:




Preanesthesia Assessment Clinic


The preanesthesia assessment clinic has emerged as the most effective means of providing convenient “one-stop shopping” designed to (1) permit patient registration, (2) obtain a medical history and perform a physical examination, (3) promote patient teaching, (4) meet or schedule appointments with medical consultants, and (5) complete any required preoperative diagnostic testing. Successful preanesthesia assessment clinics have realized a reduction in patient anxiety, direct cost, last-minute surgical cancellations, overall length of hospitalization after surgery, and diagnostic testing, as well as improvement in patient education and a shift from inpatient to outpatient surgery status.2 The preanesthesia assessment clinic allows patients scheduled for elective surgery to be evaluated and their condition optimized sufficiently in advance of the surgery.



Timing of Patient Assessment


To allow ample time for necessary risk assessment, preoperative testing, and specialty consultations, ideal preoperative assessment for surgery and anesthesia should take place well in advance of the proposed surgery. Patients with complex medical conditions should be evaluated at least 1 week before the scheduled procedure. Because of the present economic realities, patients undergoing more complex procedures and those who have complicated medical conditions (Box 19-1)3 are frequently not admitted to the hospital before the day of surgery. Preoperative evaluation on the day of surgery can result in last-minute discoveries (e.g., of inappropriate fasting, suspected difficult airway, preexisting medical condition) that may result in surgical delay or cancellation. The timing of the preanesthesia assessment does not appear to influence outcome of anesthesia.4 In one study, no difference in the cancellation rate for ambulatory patients was observed between groups seen within 24 hours and groups seen within 1 to 30 days of the scheduled surgery.5 Governmental requirements may mandate that the preanesthesia evaluation be completed and documented by a qualified anesthesia practitioner within 48 hours prior to surgery.6 This focused evaluation must be performed by a practitioner qualified to administer anesthesia.



BOX 19-1   Conditions That Would Benefit from Early Preoperative Evaluation










Modified from Barash PG (ed). ASA Refresher Courses in Anesthesiology. Vol 24. Philadelphia: Lippincott, Williams, & Wilkins; 1996.



Chart Review


To provide the basis for and direction of the patient interview and physical assessment, the patient’s past and current medical records should be reviewed preoperatively. Ideally the anesthesia provider will have the opportunity to review the patient’s medical records before the interview with the patient or caregiver.




Patient Chart or Electronic Medical Record


A review of the current medical record includes verifying that the surgical and anesthesia consents are accurate and complete. The names of the patient and surgeon, the date, and the proposed procedure should be matched with those on the operating room schedule. Demographic or baseline data, such as the age, height, and weight of the patient, can often be obtained from the admitting record. Vital-sign trends and input-output totals are transcribed from graphic flow sheets, which may also contain pertinent data (e.g., daily blood glucose values for the diabetic patient).


Progress notes and consultation reports provide a valuable overview of the health history and physical status of the patient. Medical treatments, such as drug dosages and schedules, may be derived from these materials, but diagnostic test results should be obtained directly from their original sources. This retrieval of primary data prevents the possible misinterpretation of data that were transcribed incorrectly. Knowledge gleaned from a review of progress notes and consultative reports enables the anesthesia provider to formulate supplementary questioning, seek further specialist consultations, or obtain additional diagnostic testing as needed.


Baseline data concerning the patient, such as cultural diversity, coping mechanisms, or patient limitations (e.g., hearing impairment), can often be derived from nursing notes and can effectively guide the anesthesia provider in conducting a thorough preoperative interview. Increasingly the anesthetist must be able to appropriately interact with culturally diverse populations to properly evaluate and educate patients.


A preanesthesia questionnaire is included on the patient’s chart (Figure 19-1). This questionnaire should be part of the admission paperwork to be completed by the patient or the patient’s caregiver and consists of a concise checklist regarding the patient’s health history and medical care. When properly completed and readily available on the chart, the preanesthesia questionnaire enables the anesthesia provider’s visit with the patient to be accomplished more efficiently. Interview questions and physical assessment are appropriately directed toward abnormal findings and areas of concern.




Patient Interview


The preoperative interview may be conducted in person or by telephone. The in-person patient interview is preferred, but for patients who are unable to visit the hospital setting (e.g., who live far from the hospital or have transportation constraints), an opportunity to participate in a telephone interview should be made available. Regardless of the location or approach used, the interview promotes a trusting relationship between the patient and anesthesia provider. When the interview is performed in a caring and unhurried manner, the patient’s degree of trust and confidence in anesthesia care is enhanced. Furthermore, compliance with perioperative instructions is increased when the patient is treated with respect; an example of such respect is using the surname (Mr. Smith, Mrs. Jones) unless instructed differently by the patient.


The title of the anesthesia provider and his or her specific role in the patient’s perioperative care should also be defined. The patient is entitled to know whether the interviewer is a Certified Registered Nurse Anesthetist, student registered nurse anesthetist, anesthesiologist, or medical resident in anesthesiology. The professional appearance and attitude of the anesthesia provider also can create a positive impression during the preoperative visit.


The environment of the preoperative interview should be staged to maximize the quality and effectiveness of the interaction. Adequate lighting enhances effective communication with the patient. Distractions such as an operating television set can be eliminated. The anesthesia provider should ensure that the time and location of the interview, whether it occurs in person or by telephone, are convenient and private for the patient. A return visit or call may be necessary if the patient is eating or receiving medical therapy.


Because the preoperative interview is a private interaction between the patient and the anesthesia provider, a tactful request that visitors remain outside the interview area, unless the patient wishes family members to be present, will be necessary. Otherwise, the patient may not volunteer confidential health information, such as a history of substance abuse or sexual history. In certain situations, however, assistance from a family member or caregiver is required. The health history may be provided, for example, by the parent of a pediatric patient or by an interpreter for a patient with cognitive or language barriers.


The patient interview is designed to achieve specific objectives (Box 19-2).7 The interview process, along with patient education, yields beneficial consequences of reduced patient anxiety and increased patient satisfaction. A valuable step in preparing the patient or responsible caregivers (e.g., family members, legal guardian) for the scheduled surgery includes an educational process during which the staff counsels the patient concerning fundamental perioperative issues (Box 19-3).7 Reinforcing information to the patient verbally and in writing is essential to gaining patient compliance. Coordinating the patient’s visit to the preanesthesia assessment clinic to include educational time is ideal for the patient.



BOX 19-2   Objectives of the Preoperative Interview




Modified from Cassidy J, Marley RA. Preoperative assessment of the ambulatory patient. J Perianesth Nurs. 1996;11(5):334-343.



BOX 19-3   Patient Education Objectives




• Promote interactive communication between patient and care provider.


• Encourage patient participation in making decisions about perioperative care.


• Maximize and enhance patient self-care skills and participation in continuing care during the postoperative phase.


• Increase the patient’s ability to cope with his or her health status.


• Increase patient compliance with perioperative care.


• Provide individualized preoperative instructions regarding the following:



• Detail the process of arrival and registration on arrival to the surgical facility (i.e., time and location of arrival).


• Review advance directive information as required by law in some states.


• Explain the surgical facility policies to the patient and family.


Modified from Cassidy J, Marley RA. Preoperative assessment of the ambulatory patient. J Perianesth Nurs. 1996;11(5):334-343.



Medical History


The extent of a patient’s health history depends partly on the amount of information available in the chart before surgery. If the surgeon has already documented a thorough medical history and physical examination, the interview can focus on confirming major findings and obtaining information that directly relates to the anesthetic management of the patient. The anesthesia provider must obtain and document a detailed health history, however, if the history is unavailable in the chart during the preoperative visit.


The health history should be obtained in an organized and systematic way, as with the preanesthesia questionnaire, to minimize possible omission of important data. Open-ended and direct questions targeting each category of the checklist can be posed. With this approach, more detailed and graded responses are elicited from the patient. To avoid overwhelming or confusing a patient, questions are asked separately and formulated in comprehensible or layperson’s terms.




Anesthetic History


Past anesthetic experiences are often not as easily defined as the surgical history. It is vitally important to determine the reaction of a patient to previously administered anesthetics. Adverse reactions to anesthetic agents and techniques (e.g., prolonged vomiting, difficult airway, malignant hyperthermia, postoperative delirium, anaphylaxis, and cardiopulmonary collapse) may have simply been an annoyance to the patient or could have been life threatening. Preoperative knowledge of these complications allows the anesthetic approach to be modified and the recurrence of the complication thereby prevented. Causative factors are also thoroughly investigated in patients who note that a previous operation was aborted. Difficulties with airway management can alter the approach to endotracheal intubation, if indicated. Vague reports of fever and convulsions merit further investigation to rule out an episode of malignant hyperthermia.




Drug History


A preoperative drug history provides an excellent guide for the direction and depth of the patient interview and assessment. Drug dosages, schedules, and durations of treatment are reviewed and the patient questioned about the purpose and effectiveness of these medications. An interview with a patient receiving β-adrenergic blockers, for example, can focus in greater detail on the cardiovascular system. Patients on medications for hypertension or angina pectoris require further investigation and possibly specialty consultation if they have not been recently evaluated.




Adverse Drug Effects and Interactions

During the preoperative evaluation, current drug therapy must be carefully reviewed for side effects and potential interactions with anesthetic agents. Table 19-1 lists selected drugs and their potential anesthetic interactions.4,8–17 One drug-management strategy is to discontinue particular drugs preoperatively in the hope of reducing the potential for adverse interactions. The therapeutic benefits of these drugs are weighed against the risks of abrupt discontinuation. Abrupt discontinuation of long-standing medication may lead to the development of undesirable withdrawal symptoms. With occasional exceptions, the majority of medications are continued preoperatively. Should a decision be made to withhold a particular drug before surgery, sufficient time should be allowed for metabolic clearance (ideally three to five half-lives).8



TABLE 19-1


Potential Drug Interactions Affecting Perianesthesia Care


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ECG, Electrocardiogram; INR, international normalized ratio (prothrombin time); IV, intravenous; PT, prothrombin time; PTT, partial thromboplastin time; GI, gastrointestinal.


Data from Doak GJ. Discontinuing drugs before surgery. Can J Anaesth. 1997;44(5 Pt2):R112-R123; Pass SE, Simpson RW. Discontinuation and reinstitution of medications during the perioperative period. Am J Health Syst Pharm. 2004;61(9):899-912; Schirmer U, Schurmann W. Preoperative administration of angiotensin-converting enzyme inhibitors. Anaesthesist. 2007;56(6):557-561; Baillard C. Preoperative management of chronic medications. Ann Fr Anesth Reanim. 2005(11-12);24:1360-1374; Huyse FJ, et al. Psychotropic drugs and the perioperative period: a proposal for a guideline in elective surgery. Psychosomatics. 2006(1);47:8-22; Fleischmann KE, et al. 2009 ACCF/AHA focused update on perioperative beta blockade: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines. Circulation. 2009;120(21):2123-2151; Hoeks SE, Poldermans D. European Society of Cardiology 2009 guidelines for preoperative cardiac risk assessment and perioperative cardiac management in noncardiac surgery: key messages for clinical practice. Pol Arch Med Wewn. 2010;120(7-8):294-299; Lieb K, Selim M. Preoperative evaluation of patients with neurological disease. Semin Neurol. 2008; 28(5):603-610; De Hert S, et al. Preoperative evaluation of the adult patient undergoing non-cardiac surgery: guidelines from the European Society of Anaesthesiology. Eur J Anaesthesiol. 2011;28(10):684-722; White CM, et al. Effect of preoperative angiotensin converting enzyme inhibitor or angiotensin receptor blocker use on the frequency of atrial fibrillation after cardiac surgery: a cohort study from the atrial fibrillation suppression trials II and III. Eur J Cardiothorac Surg. 2007;31(5):817-820; Whinney C: Perioperative medication management: general principles and practical applications. Cleve Clin J Med. 2009;76(suppl 4): S126-S132.




Latex Sensitivity


Patient sensitivity to latex products has recently been identified as a frequent basis of allergic reaction. Up to 20% of intraoperative anaphylactic reactions have been attributed to latex sensitivity.18 The preoperative questioning of patients should include inquiry regarding specific latex sensitivity or allergy. Patients at increased risk for latex sensitivity should be cared for in a no-latex setting and scheduled as the first case of the day to reduce the likelihood of aeroallergen latex exposure. The diagnosis of latex allergy is based on the findings of the history and physical examination and if necessary, in vivo (skin-prick test is the most sensitive) and in vitro testing. Preoperative testing is indicated only when there is a family history of reactions or when patients report experiencing symptoms such as a rash, swelling, or wheezing when exposed to latex.19 Patients at high risk for latex sensitivity include those with a history of the following18:




Social History


The addictive nature of tobacco and alcohol, as well as illegal drugs, exerts a detrimental influence on several aspects of life in the United States.



Certain drugs, despite their social or recreational application, may be associated with adverse and life-threatening consequences with long- or short-term use or overdose. The social history provides an excellent opportunity to explore the extent of self-medication. Open-ended questions, posed in a professional and nonjudgmental manner, are most likely to elicit detailed information from the patient. At this time, the patient can also be educated about the adverse consequences of substance abuse; especially as such substances affect anesthetic care.



Tobacco Use


Many patients arrive for anesthesia and surgery with a history of tobacco smoking. In the United States, some disturbing statistics are associated with this form of substance abuse:



The inhaled components of tobacco smoke lead to multiple pathophysiologic changes within the body. Nicotine and carbon monoxide are just two of the more than 6000 noxious components that have been identified in tobacco smoke.26 Nicotine, a toxic alkaloid, produces ganglionic stimulant effects and is the tobacco component that affects the cardiovascular system.27 Acute side effects of nicotine include increased heart rate, blood pressure, myocardial contraction, myocardial oxygen consumption, myocardial excitement, and peripheral vascular resistance. Net effects of nicotine’s cardiovascular influence include impaired coronary blood flow and an adverse myocardial oxygen supply/demand ratio.28 Carbon monoxide readily occupies the oxygen-binding sites of hemoglobin (approximately 250 to 300 times greater affinity for hemoglobin than oxygen).29 Oxygen transport to the tissues and resultant oxygen use is thereby drastically reduced. In the heavy smoker, carboxyhemoglobin may be as high as 15%, which effectively reduces the patient’s oxyhemoglobin percentage accordingly. The adverse effects of nicotine on the cardiovascular system and carbon monoxide on oxygen-carrying capacity are short lived (half-life of nicotine is 40 to 60 minutes30; half-life of carbon monoxide if room air is breathed is 130 to 190 minutes).31


Patients should be instructed to stop smoking at least 12 to 48 hours before surgery. Short-term (e.g., 12 hours) preoperative abstinence from tobacco smoke reduces the deleterious effects of nicotine and carbon monoxide on cardiopulmonary function.32 Smoking cessation for even 1 night before surgery reduces heart rate, blood pressure, and circulating catecholamine levels33 and allows carboxyhemoglobin values to return to normal levels.34


Patients who smoke have a higher incidence (a nearly sixfold increase35) of postoperative pulmonary complications (pneumonia and atelectasis).36 A smoking history of more than 20 pack years equates to an increased risk of perioperative complications.37 Smoking cessation of less than 4 weeks does not reduce the risk of postoperative respiratory complication.4,38 Longer periods of smoking cessation (8 weeks or longer) result in a marked improvement in pulmonary mechanics (e.g., enhanced ciliary function, decreased mucous secretion and small airway obstruction, and enhanced immune function).39 Patients who stopped smoking less than 2 months before surgery had nearly four times the pulmonary complications (e.g., purulent sputum, secretion retention, bronchospasm, pleural effusion, pneumothorax, segmental pulmonary collapse, pneumonia) of those who abstained from smoking for longer than 2 months.40 However, even short-term smoking cessation is effective in reducing postoperative complications when compared with patients who continued to smoke up until the time of surgery.39 A reduction in postoperative wound-related complications occurs in patients who stop smoking preoperatively.41 Patients who smoke should be advised to quit even immediately prior to surgery, without fear of worsening pulmonary outcomes or increasing psychological stress as a result of acute abstinence.42 Effective interventions, including behavioral support and nicotine replacement therapy, should be made available to smokers considering abstinence at this time.43


The influence of environmental tobacco smoke (also known as secondhand or passive smoke) on children has been found to produce disturbing respiratory consequences, including increased reactive airway disease, abnormal results of pulmonary function tests, and increased respiratory tract infections.44,45 The perioperative complications in children exposed to smoke include laryngospasm, coughing on induction or emergence, breath holding, postoperative oxyhemoglobin desaturation, and hypersecretion.46



Alcohol Intake


An estimated 14 million Americans are dependent on alcohol, with 105,000 deaths annually attributed to alcohol abuse.47 Perioperative complications, such as arrhythmias, infection, and alcohol withdrawal syndrome, are increased two- to fivefold in chronic excessive alcohol users.48 Postoperative complications can by reduced with 4 or more weeks of abstinence prior to surgery.49 Information regarding the type and amount of alcohol regularly consumed and the frequency of consumption is important in the evaluation for anesthesia and surgery. Often an accurate assessment of a patient’s alcohol intake may be difficult to obtain. The Alcohol Use Disorders Identification Test (AUDIT), a self-reporting questionnaire designed to identify problem drinkers, can be incorporated into the preoperative interview of suspected problem drinkers.50 A less confrontational and a reliable approach to evaluating a patient’s potential for an alcohol problem uses the mnemonic CAGE, which refers to the following four questions51:



A patient reporting more than two positive responses is at high risk for alcoholism and an increased likelihood of experiencing withdrawal symptoms.52 Both AUDIT and CAGE have been shown to be effective in identifying the abusive alcohol consumer.53


In the heavy drinker, it is important to determine whether the patient has experienced seizures, abrupt withdrawal syndrome, or delirium tremens as a consequence of alcohol abuse. Clinical signs suggestive of alcohol withdrawal include increased hand tremors, autonomic hyperactivity (e.g., sweating, tachycardia, systolic hypertension), insomnia, anxiety, restlessness, nausea or vomiting, transient hallucinations (visual, tactile, or auditory), psychomotor agitation, and grand mal seizures.52


Chronic alcohol abuse results in the development of tolerance, physical dependence, and multisystem organ dysfunction. Tolerance to alcohol is evidenced by a resistance or cross-tolerance to other central nervous system (CNS) depressants. For example, the anesthetic requirement of hypnotics, opioids, and inhalation agents is increased in the chronic alcoholic; however, exaggerated responses to anesthetic agents are likely during periods of acute intoxication or advanced alcoholism. This effect is attributed to the additive depressant effects of alcohol and anesthetic agents. Enzymatic function and plasma albumin concentrations may also be reduced in patients with alcoholic hepatic insufficiency. As a result, greater circulating concentrations of unbound intravenous agents may result in an exaggerated and prolonged drug effect.54 This enhanced drug response has not been shown to occur with propofol in patients with moderate liver cirrhosis.55


An insidious progression of multisystem organ dysfunction is also characteristic of long-term alcohol abuse. Numerous illnesses are attributable to the toxic adverse effects of advanced alcoholism on overall health and nutrition. Predictably, postoperative morbidity and mortality rates are increased in alcoholic patients as a result of poor wound healing, infection, bleeding, pneumonia, and further hepatic deterioration.56,57



Illicit Drug Use


Use of illicit drugs (e.g., cocaine, cannabis, “crack,” lysergic acid diethylamide-25 [LSD], amphetamines, heroin, hallucinogens, inhalants, prescription-type psychotherapeutics used nonmedically) is a significant healthcare issue in the United States. The most popular recreational drugs continue to be cocaine and marijuana. Monthly drug abuse among Americans include 17 million marijuana users, 7 million prescription-type psychotherapeutic nonmedical drug users, 1.5 million cocaine users, 1.2 million hallucinogen users, and 731,000 methamphetamine users in 2010.20 Americans use 80% of all opioids available in the world.58 The use of these substances increases the risk for adverse consequences and drug interactions during anesthesia. An accurate illicit drug history is often difficult to obtain because of the patient’s fear of legal reprisal or refusal to believe a drug problem exists. During the physical examination, the anesthesia provider should look for signs that indicate illicit drug use by the patient. A diagnosis of recent or continuing drug abuse should be suspected in patients exhibiting the following on physical examination59:



Primary concerns for the anesthesia provider are the likelihood of the patient exhibiting acute abuse or possible withdrawal syndrome.60 Signs and symptoms of acute abuse of the more common substances are listed in Box 19-4.59,60 Elective surgery should be delayed or canceled in patients suspected of being under the influence of an illicit drug until further patient evaluation can be performed. Suspicion of acute substance abuse should be followed up with a urine screen for drug identification. Abstinence syndrome typically exhibits increased sympathetic and parasympathetic responses resulting in hypertension, tachycardia, abdominal cramping and diarrhea, tremors, anxiety, irritability, lacrimation, mydriasis, algid sweat, and yawning.61



BOX 19-4   Signs and Symptoms of Acute Substance Abuse






From Cheng DCH. The drug addicted patient. Can J Anaesth. 1997;44(5 Pt2):R101-R111; Cavaliere F, et al. Anesthesiologic preoperative evaluation of drug addicted patient. Minerva Anestesiol. 2005;71(6):367-371. LSD, Lysergic acid diethylamide-25; PCP, phencyclidine.




Herbal Dietary Supplements


Patients should be questioned regarding their use of nonprescription herbal medications to determine the herb’s name, the duration of herbal therapy, and the dose taken. If patients are in doubt as to the herbal medications they are taking, they should be encouraged to bring the herbal products with them to their preoperative workup. Certain herbal products are known to influence blood clotting, affect blood glucose levels, produce CNS stimulation or depression, or interact with psychotropic drugs (Table 19-2).66,67



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May 31, 2016 | Posted by in ANESTHESIA | Comments Off on Preoperative Evaluation and Preparation of the Patient

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