The dilemma of immediate preoperative hypertension: to treat and operate, or to postpone surgery?

Perioperative cardiac risk reduction in non cardiac surgery

For patients undergoing nonemergent noncardiac surgery, care must be taken to identify patients at increased risk of major adverse cardiovascular events, as these remain a significant source of perioperative morbidity and mortality. Identification of at-risk patients requires careful attention to risk factors including assessment of functional status, medical comorbidities, and a medication assessment. After identification, to minimize perioperative cardiac risk, care should be taken through a combination of appropriate medication management, close monitoring for cardiovascular ischemic events, and optimization of pre-existing medical conditions. There are multiple society guidelines that aim to mitigate risk of cardiovascular morbidity and mortality in patients undergoing nonemergent noncardiac surgery. However, the rapid evolution of medical literature often creates gaps between the existing evidence and best practice recommendations. In this review, we aim to reconcile the recommendations made in the guidelines from the major cardiovascular and anesthesiology societies from the USA, Canada, and Europe, and to provide updated recommendations based on new evidence.

Perioperative Cardiac Risk Reduction in Noncardiac Surgery

Major adverse cardiovascular events are a significant source of morbidity and mortality in the perioperative setting, estimated to occur in approximately 5% of patients undergoing nonemergent noncardiac surgery. To minimize the incidence and impact of these events, careful attention must be paid to preoperative cardiovascular assessment to identify patients at high risk of cardiovascular complications. Once identified, cardiovascular risk reduction is achieved through optimization of medical conditions, appropriate management of medication, and careful monitoring to allow for early identification of-and intervention for-any new conditions that would increase the risk of adverse cardiovascular outcomes. The major cardiovascular and anesthesiology societies in the United States, Europe, and Canada have published guidelines for perioperative management of patients undergoing noncardiac surgery. However, since publication of these guidelines, there has been a practice-changing evolution in the medical literature. In this review, we attempt to reconcile the recommendations made in these 3 comprehensive guidelines, while updating recommendations, based on new evidence, when available.

Anesthetic management of hypertensive patients

It is important for the clinicians to have a clear understanding of the anesthetic implications and increased risks due to hypertension to ensure safe surgical procedures in hypertensive patients. Preoperative hypertension is associated with greater intraoperative hemodynamic lability and an increased risk of perioperative cardiovascular complications. In addition to the patients’ baseline blood pressure (BP), the presence and severity of target organ damage and cardiovascular comorbidities should be evaluated preoperatively. Delaying surgery in hypertensive patients may be justified if there is an evidence of target organ damage that can be improved by such a delay. Further evaluation of suspected target organ damage before the surgery is also justified. Except withholding angiotensin-converting enzyme inhibitors/angiotensin receptor blockers 10 to 24 hours before the surgery, the continuation of preoperative antihypertensive therapy is generally recommended. Though maintaining perioperative BP within the range of 80%–90% to 110%–120% of the baseline BP (permissible BP decrease/increase ≤10%–20%) is generally recommended, an individualized and pathophysiology-based approach to control BP might be the best option throughout the perioperative period. In other words, BP targets in the perioperative period should be determined based on the type of surgery, patients’ baseline BP, risks of hypotension-related organ ischemia, and hypertension-related bleeding.

The association between preinduction arterial blood pressure and postoperative cardiovascular, renal, and neurologic morbidity, and in-hospital mortality in elective noncardiac surgery: an observational study

BACKGROUND

The association between preinduction blood pressure (BP) and postoperative outcomes after noncardiac surgery is poorly understood. Whether this association depends on the presence of risk factors for poor cardiovascular outcomes remains unclear. Accordingly, we evaluated the association between preinduction BP and its different components; isolated systolic hypertension (ISH) and wide pulse pressure (WPP), and postoperative complications in patients with and without revised cardiac risk index (RCRI) components.

METHODS

We analysed consecutive patients undergoing elective noncardiac surgery at Cleveland Clinic. Separate analyses were undertaken for patients with and without any RCRI components. Preinduction BP was assessed both continuously and according to hypertension stages. Logistic regression was used to assess the association between the BP values and composite of in-hospital mortality as well as cardiovascular, renal, and neurologic morbidity. We considered the following potential confounding factors in our analysis; year of surgery, age, sex, race, BMI, and American College of Cardiology/American Heart Association surgical procedure risk classification.

RESULTS

Of 58 276 patients, 10 512 had one or more RCRI components. For those with no RCRI, no significant relationship was found between preinduction BP and outcome after adjustment for confounders. For patients with RCRI, the adjusted incidence was the greatest among those with normal preinduction SBP and DBP of less than 70 mmHg. Among patients with preinduction DBP greater than 75 mmHg, risk rose slightly with increasing SBP. However, we found no association between preinduction hypertension stages, ISH, or WPP and the composite outcome in patients with and without RCRI.

CONCLUSION

Preinduction low DBP less than 70 mmHg or SBP greater than 160 mmHg and not ISH, nor WPP were associated with an increased risk of postoperative complications in noncardiac surgery patients with one or more RCRI components.

Preoperative Assessment of Older Adults

Older patients undergoing surgery have reduced physiologic reserve caused by the combined impact of physiologic age-related changes and the increased burden of comorbid conditions. The preoperative assessment of older patients is directed at evaluating the patient's functional reserve and identifying opportunities to minimize any potential for complications. In addition to a standard preoperative evaluation that includes cardiac risk and a systematic review of systems, the evaluation should be supplemented with a review of geriatric syndromes. Age-based laboratory testing protocols can lead to unnecessary testing, and all testing should be requested if indicated by underlying disease and surgical risk.

Cohort study of preoperative blood pressure and risk of 30-day mortality after elective non-cardiac surgery

Background

Preoperative blood pressure (BP) thresholds associated with increased postoperative mortality remain unclear. We investigated the relationship between preoperative BP and 30-day mortality after elective non-cardiac surgery.

Methods

We performed a cohort study of primary care data from the UK Clinical Practice Research Datalink (2004-13). Parsimonious and fully adjusted multivariable logistic regression models, including restricted cubic splines for numerical systolic and diastolic BP, for 30-day mortality were constructed. The full model included 29 perioperative risk factors, including age, sex, comorbidities, medications, and surgical risk scale. Sensitivity analyses were conducted for age (>65 vs <65 years old) and the timing of BP measurement.

Results

A total of 251 567 adults were included, with 589 (0.23%) deaths within 30 days of surgery. After adjustment for all risk factors, preoperative low BP was consistently associated with statistically significant increases in the odds ratio (OR) of postoperative mortality. Statistically significant risk thresholds started at a preoperative systolic pressure of 119 mm Hg (adjusted OR 1.02 [95% confidence interval (CI) 1.01-1.02]) compared with the reference (120 mm Hg) and diastolic pressure of 63 mm Hg [OR 1.24 (95% CI 1.03-1.49)] compared with the reference (80 mm Hg). As BP decreased, the OR of mortality risk increased. Subgroup analysis demonstrated that the risk associated with low BP was confined to the elderly. Adjusted analyses identified that diastolic hypertension was associated with increased postoperative mortality in the whole cohort.

Conclusions

In this large observational study we identified a significant dose-dependent association between low preoperative BP values and increased postoperative mortality in the elderly. In the whole population, elevated diastolic, not systolic, BP was associated with increased mortality.

Systemic hypertension and non-cardiac surgery

Primary systemic hypertension affects 10%–25% of individuals presenting for surgery and anaesthesia and constitutes an important cause of cancellation of elective surgeries. Much of the fear stems from the fact that hypertension may lead to adverse perioperative outcomes. Although long-standing hypertension increases the risk of stroke, renal dysfunction or major adverse cardiovascular events, the same is usually not seen in the perioperative period if blood pressure is <180/110 mmHg and this has been the overriding theme in the recent guidelines on perioperative blood pressure management. Newer concepts include isolated systolic hypertension and pulse pressure hypertension that are increasingly used to stratify risk. The aim of this review is to focus on the adult patient with chronic primary systemic hypertension posted for elective non-cardiac surgery and outline the perioperative concerns.

Preoperative Assessment of the Patient with Cardiac Disease Undergoing Noncardiac Surgery

The American College of Cardiology/American Heart Association has published Guidelines on Perioperative Evaluation. Preoperative evaluation should focus on identifying patients with symptomatic and asymptomatic coronary artery disease. The guidelines advocate using the American College of Surgeons National Surgical Quality Improvement Project Risk Index to determine perioperative risk. Diagnostic testing should be reserved for those at increased risk with poor exercise capacity. Indications for coronary interventions are the same in the perioperative period as in the nonoperative setting. In patients with a prior coronary stent, optimal antiplatelet therapy and timing of elective noncardiac surgery is evolving.

The measurement of adult blood pressure and management of hypertension before elective surgery: Joint Guidelines from the Association of Anaesthetists of Great Britain and Ireland and the British Hypertension Society

This guideline aims to ensure that patients admitted to hospital for elective surgery are known to have blood pressures below 160 mmHg systolic and 100 mmHg diastolic in primary care. The objective for primary care is to fulfil this criterion before referral to secondary care for elective surgery. The objective for secondary care is to avoid spurious hypertensive measurements. Secondary care should not attempt to diagnose hypertension in patients who are normotensive in primary care. Patients who present to pre-operative assessment clinics without documented primary care blood pressures should proceed to elective surgery if clinic blood pressures are below 180 mmHg systolic and 110 mmHg diastolic.

Intraoperative cardiac emergencies

Intraoperative cardiac emergencies require prompt recognition and management in order to optimize patient safety and recovery. This article addresses the perioperative management of hypertension, myocardial infarction, arrhythmias, autonomic dysreflexia, tamponade, and tension pneumothorax. These complications can occur in patients with underlying coexisting disease, but can also occur in surgical patients regardless of the underlying disorder.

Does premedication with dexmedetomidine provide perioperative hemodynamic stability in hypertensive patients?

Background

Perioperative hemodynamic fluctuations are seen more often in hypertensive patients than in normotensive patients. The purpose of our study was to investigate the perioperative hemodynamic effects of dexmedetomidine and midazolam used for premedication in hypertensive patients relative to each other and in comparison to normotensive patients.

Methods

One-hundred-forty female, normotensive or hypertensive patients undergoing myomectomies or hysterectomies. They were randomly enrolled into the subgroups: Group ND (normotensive-dexmedetomidine); Group HD (hypertensive-dexmedetomine); Group NM (normotensive-midazolam); Group HM (hypertensive- midazolam). Dexmedetomidine was administered at a concentration of 0.5 μg.kg⁻¹, and midazolam was administered at a concentration of 0.025 μg.kg⁻¹ via intravenous (IV) infusion before the induction of anaesthesia. Haemodynamic parameters were recorded at several times (T_beginning, T_{preop5 min}, T_{preop 10 min}, T_induction, T_intubation, T_{intubation5 min}, T_{initial surgery}, T_{surgery 15 min}, T_{surgery 30 min}, T_extubation, T_{extubation 5 min}). Propofol amount for induction, time between induction and initial surgery, demand of antihypertensive therapy, rescue atropine were recorded. Quantitative clinical and demographic characteristics were compared using One Way ANOVA. The values were compared using One-way Analysis of Variance. Additionally periodic variations were examined by One way Repeated Measures Analysis of Variance for groups separately.

Results

SBP was significantly different between normotensive and hypertensive groups at the following time points: T_{preop 5 min}, T_{preop 10 min}, T_induction, T_intubation, T_{intubation 5 min} and T_{initial surgery}. MBP was significantly different in the hypertensive groups at T_induction, T_intubation, T_{intubation 5 min,} T_{initial surgery}, T_{surgery 15 min}, T_{surgery 30 min,} T_extubation and T_{extubation 5 min}. The perioperative requirements for antihypertensive drugs were significantly higher in Group HM.

Conclusion

In the hypertensive patients, dexmedetomidine premedication provides better hemodynamic stability compared with midazolam, and because it decreases the antihypertensive requirements, its use might be beneficial.

Trial registration

Trial registration: Clinicaltrials.gov identifier: NCT02058485.

Optimal perioperative management of arterial blood pressure

Perioperative blood pressure management is a key factor of patient care for anesthetists, as perioperative hemodynamic instability is associated with cardiovascular complications. Hypertension is an independent predictive factor of cardiac adverse events in noncardiac surgery. Intraoperative hypotension is one of the most encountered factors associated with death related to anesthesia. In the preoperative setting, the majority of antihypertensive medications should be continued until surgery. Only renin-angiotensin system antagonists may be stopped. Hypertension, especially in the case of mild to moderate hypertension, is not a cause for delaying surgery. During the intraoperative period, anesthesia leads to hypotension. Hypotension episodes should be promptly treated by intravenous vasopressors, and according to their etiology. In the postoperative setting, hypertension predominates. Continuation of antihypertensive medications and postoperative care may be insufficient. In these cases, intravenous antihypertensive treatments are used to control blood pressure elevation.

Perioperative evaluation and management of cardiac disease in the ambulatory surgery setting

Preoperative cardiac evaluation focuses on risk assessment and reduction. Diagnostic testing and interventions are used only when the risk of adverse outcomes is high and intervention will lower the risk. The evaluation is performed in a stepwise fashion according to guidelines in the literature.

Hemodynamic changes following endotracheal intubation with glidescope(®) video-laryngoscope in patients with untreated hypertension

Background:

Tracheal intubation can be associated with considerable hemodynamic changes, particularly in patients with uncontrolled hypertension. The GlideScope^® video-laryngoscope (GVL) is a novel video laryngoscope that does not need direct exposure of the vocal cords, and it can also produce lower hemodynamic changes due to lower degrees of trauma and stimuli to the oropharynx than a Macintosh direct laryngoscope (MDL).

Objectives:

The aim of this clinical trial was to compare hemodynamic alterations following tracheal intubation with a GVL and MDL in patients with uncontrolled hypertension.

Patients and Methods:

Sixty patients who had uncontrolled hypertension and scheduled for elective surgery requiring tracheal intubation, were randomly assigned to receive intubated with either a GVL (n = 30) or a MDL (n = 30). Intubation time, heart rate, rate pressure product (RPP), and mean arterial blood pressure (MAP), were compared between the two groups at; baseline, following induction of anesthesia, after intubation, and at one minute intervals for 5 minutes.

Results:

A total of 59 patients finished the study. Intubation time was longer in the GVL group (9.80 ± 1.27 s) than in the MDL group (8.20 ± 1.17 s) (P < 0.05). MAP, pulse rate, and RPP were lower in the GVL than the MDL group after endotracheal intubation (P < 0.05). MAP, heart rate, and RPP returned to pre-intubation values at 3 and 4 minutes after intubation in the GVL and MDL groups, respectively (P < 0.05).

Conclusions:

Hemodynamic fluctuations in patients with uncontrolled hypertension after endotracheal intubation were lower with the GVL than the MDL technique.

Home blood pressure monitoring in an anaesthetic pre-admission clinic

We suspected that many high blood pressure measurements taken in our anaesthetic pre-assessment clinic and immediately prior to induction of anaesthesia were unusually elevated due to a 'white coat' effect. These high blood pressure measurements were causing late cancellations of surgery, even though white coat measurements may not be representative of the patient's usual blood pressure or of their risk of end-organ damage due to hypertension. In this audit, patients with high blood pressure in our pre-admission clinic were provided with training and a home blood pressure monitor to use prior to surgery. These were compared to the pre-admission clinic measurements to determine the incidence of white coat hypertension. We also compared home to general practice blood pressure monitoring where possible. Fifty-two patients were provided with monitors. Fifty-one of these took at least five measurements at home. Thirty-four (66%) patients had average measurements at home at least 20 mmHg lower than pre-admission clinic measurements. A total of 33% of general practice clinic measurements were also ≥ 20 mmHg higher than average home measurements. White coat hypertension was common in our audit population. Relying on average home blood pressure measurements rather than 'one off' in-hospital measurements may have helped to prevent the postponement or cancellation of surgery for 13 patients who had recorded blood pressure ≥ 180/110 mmHg in our pre-admission clinic.

Cardiovascular anesthetic complications and treatment in oral surgery

Perioperative hypertension is a common problem. If hypertension is left untreated in patients at risk, infarctions and stroke are possible. There are limited choices of antihypertensive agents for the office. Aggressive antihypertensive therapy is not indicated because most of the episodes seen in the office are hypertensive urgencies and not emergencies. Hypotension is usually managed by decreasing the depth of anesthesia, intravenous fluids, and then vasopressors, typically ephedrine or phenylephrine. Consider treatment of hypotension whenever the mean arterial pressure decreases less than 60 mm Hg.

Perioperative hypertension: defining at-risk patients and their management

Hypertension is an extremely pervasive condition that affects a large percentage of the world population. Although guidelines exist for the treatment of the patient with elevated blood pressure, there remains a paucity of literature and accepted guidelines for the perioperative evaluation and care of the patient with hypertension who undergoes either cardiac or noncardiac surgery. Of particular importance is defining the patients most vulnerable to complications and the indications for immediate and rapid antihypertensive treatment and/or cancellation of surgery to reduce these risks in each of the three perioperative settings: preoperative, intraoperative, and postoperative. This review also examines the parenteral antihypertensive medications most commonly administered in the perioperative setting.

Medical complications of obesity and optimization of the obese patient for colorectal surgery

Obesity is a medical epidemic with an enormous impact on disease prevalence and health care utilization. In the preoperative period, an awareness of medical issues associated with obesity is an important part of the planning for surgical procedures. The authors highlight the diagnostic and treatment options for medical conditions commonly affecting the obese patient including diabetes, hypertension, coronary artery disease, and deep venous thrombosis.

Incidence of preoperative high blood pressure in cataract surgery among hypertensive and normotensive patients

Incidence of preoperative rise in blood pressure (BP) in cataract surgery among hypertensive and normotensive patients.

Management of perioperative hypertensive urgencies with parenteral medications

BACKGROUND

Hypertension is the major risk factor for cardiovascular (CV) disease such as myocardial infarction (MI) and stroke. This risk is well known to extend into the perioperative period. Although most perioperative hypertension can be managed with the patient's outpatient regimen, there are situations in which oral medications cannot be administered and parenteral medications become necessary. They include postoperative nil per os status, severe pancreatitis, and mechanical ventilation. This article reviews the management of perioperative hypertensive urgency with parenteral medications.

METHODS

A PubMed search was conducted by cross-referencing the terms "perioperative hypertension," "hypertensive urgency," "hypertensive emergency," "parenteral anti-hypertensive," and "medication." The search was limited to English-language articles published between 1970 and 2008. Subsequent PubMed searches were performed to clarify data from the initial search.

RESULTS

As patients with hypertensive urgency are not at great risk for target-organ damage (TOD), continuous infusions that require intensive care unit (ICU) monitoring and intraarterial catheters seem to be unnecessary and a possible misuse of resources.

CONCLUSIONS

When oral therapy cannot be administered, patients with hypertensive urgency can have their blood pressure (BP) reduced with hydralazine, enalaprilat, metoprolol, or labetalol. Due to the scarcity of comparative trials looking at clinically significant outcomes, the medication should be chosen based on comorbidity, efficacy, toxicity, and cost.

[Hypertension and anesthesia: consensus statement of the Catalan Associations of Anesthesiology and Hypertension]

The prevalence of hypertension is high in the surgical population. Differing practices and the absence of consensus among physicians involved in caring for hypertensive patients has made it one of the most frequent reasons for cancelling scheduled surgery. The aim of this consensus statement is to outline a practical approach to managing the hypertensive surgical patient. Hypertension is associated with increased risk of perioperative complications, particularly those related to systemic effects and notable fluctuations in blood pressure during surgery. Preoperative assessment should center on a search for signs and symptoms of target organ damage. The anesthesiologist should seek to reduce perioperative fluctuations in arterial pressure, particularly guarding against sustained hypotension. After surgery, antihypertensive medication should be resumed as soon as possible.

Perioperative hypertension: a review of current and emerging therapeutic agents

Perioperative hypertension is a common problem encountered by anesthesiologists, surgeons, internists, and intensivists. Surprisingly, no randomized, placebo-controlled studies exist that show that the treatment of perioperative hypertension reduces morbidity or mortality. Nevertheless, perioperative hypertension requires careful management. While sodium nitroprusside and nitroglycerin are commonly used to treat these conditions, these agents are less than ideal. Intravenous beta blockers and calcium channel blockers have particular appeal in this setting.

Drugs for the perioperative control of hypertension: current issues and future directions

The management of hypertension continues to pose important challenges. Recent developments have established the importance of more rigorous blood pressure control in the community. In the perioperative setting, hypertension has long been recognised as undesirable, although the adverse impact of high blood pressure on the acute risks of elective surgery may have been previously overstated.A number of agents and techniques are available to control blood pressure perioperatively. These include principally general and regional anaesthetics, alpha(2)-adrenoceptor agonists, peripheral alpha(1)- and beta-adrenoceptor antagonists, dihydropyridine calcium channel antagonists, dopamine D(1A)-receptor agonists (fenoldopam), and nitric oxide donors. Recent years have seen important developments in the receptor selectivity of new compounds and in pharmacokinetics, particularly esterase metabolism. The future study of genomics may enable us to identify patients at risk for hypertension-related adverse events and target therapies most effectively to these high-risk groups.