WHAT SHOULD I DO ABOUT CARDIOVASCULAR AND PULMONARY COMPLICATIONS?

Prevention remains the best way to avoid dire consequences of cardiovascular complications in arthroplasty surgeries. There have been multiple strategies to anticipate the risk based on preoperative clinical predictors and age of the patient. As per the American College of Cardiology/American Heart Association (ACC/AHA) guidelines, the patient is stratified into major, intermediate or minor risk. Surgery is postponed for patient with high-risk clinical predictors. In patients with low risk, surgery can be done without any delay. For patients with intermediate risk clinical predictors, functional status is evaluated. When functional capacity exceeds four metabolic equivalents (>4 METs), the patient is allowed to proceed with the surgery. The functional capacity of the patient is expressed in terms of METs. One MET is the resting energy expenditure, i.e., the amount of oxygen consumed by a person when he is at rest. It is approximately 3.5 mL of oxygen per kg per minute. Functional capacity is poor when the amount of oxygen consumed is less than 4 METs.

As far as detection of perioperative myocardial events is concerned, it is crucial to remember that the patient may develop silent ischaemic events without any symptoms. Hence, in addition to keeping an eye out for clinical symptoms, the surgeon should also monitor the patient by serial ECGs, cardiac-specific biomarkers, comparative echocardiography and/or nuclear studies.1 Perioperative myocardial infarction (MI) can occur either from acute thrombotic occlusion or demand ischaemia (more likely). Early intervention is crucial, and the result of primary angioplasty is better than thrombolysis in postoperative ST elevation MI. In addition to infarction and hypoxaemia, intraoperative fluid overload can result in heart failure. Pulmonary oedema is common around second postoperative day due to fluid redistribution from extravascular to intravascular space. At any rate, the surgeon should be vigilant towards the development of cardiovascular complications such as myocardial ischaemia, arrhythmia and congestive heart failure; and urgent consultation with a cardiologist should be sought.

Pneumonia, chronic obstructive pulmonary disease (COPD) exacerbation, bronchospasm, atelectasis and respiratory failure are the described postoperative pulmonary complications that cause significant morbidity and mortality after total joint arthroplasties. Fortunately, these are relatively uncommon because the surgical sites are not in the vicinity of diaphragm (the single most risk factor for development of pulmonary complications). There are certain modifiable risk factors, including surgeries lasting longer than 3 h, general anaesthesia instead of spinal anaesthesia, current tobacco use and use of intraoperative pancuronium. These risk factors should be targeted when attempting to prevent postoperative complications. Age more than 70, COPD and obstructive sleep apnea are amongst the nonmodifiable risk factors, and in such patients, a more detailed preoperative workup and perioperative care are appropriate. Incentive spirometry reduces incidence of complications, and the effect is maximum when it is started before surgery. Using epidural analgesia as a method of postoperative pain control and reducing the use of sedatives and narcotics are also helpful.

HOW TO DEAL WITH FEVER AFTER SURGERY?

First of all, you must remember that elevation of temperature after arthroplasty can be a normal process as a part of body’s natural response to surgery. It has been shown that patient’s blood contains elevated amount of cytokines (IL-1β, IL-6 and TNF α) after total joint arthroplasties. Patients react to these cytokines in a varied manner, and some patients may develop a rise in temperature. However, fever can also occur due to infection at surgical site, venous thromboembolism, pneumonia, atelectasis or urinary tract infection. A recent study recommends against doing blood culture in such patients because it is not helpful in management decisions, and it adds to health care cost and delays discharge.2 In such a scenario, the clinical acumen of the surgeon becomes more important in taking the call regarding when to investigate further. Certain parameters have been proven to predict higher positive fever evaluation, and these should be remembered as red flags – fever developing after third postoperative day, fever lasting for multiple days and a temperature higher than 39°C.3 Following these criteria, and correlating with physical findings, one can decide when and how much to investigate for fever in the postoperative period. C-reactive protein (CRP) has a bimodal fall pattern after surgery, which normalizes by second to third week. The CRP value on Day 4 is 80% reduction from the value on Postoperative Day 1. The falling trend can reassure the surgeon that it is not infective. Occasionally, procalcitonin values in early postoperative period can be helpful to rule out infection. However, these are not routinely performed due to high cost. Fever may not accompany the infection; more often, copious persisting discharge is usually suggestive of infection.

HOW TO PREVENT DEEP VEIN THROMBOSIS IN MY PATIENT?

The field of deep vein thrombosis (DVT) prophylaxis has been a confusing and controversial one since the past many years. The guidelines by the American College of Chest Physicians (ACCP) and the American Association of Orthopedic Surgeons (AAOS) were in direct conflict with each other till 2012. However, with recent revision of ACCP guidelines (ninth revision, 2012), the major recommendations are largely clear. The focus is now shifted to clinically symptomatic thromboembolic events instead of asymptomatic venography detected episodes. The new guidelines recommend that all patients should receive prophylaxis (pharmacologic agent or intermittent pneumatic compression device, IPCD) for at least 10–14 days, which could be extended up to 35 days. The pharmacologic agents include low molecular weight heparins (LMWH), fondaparinux, apixaban dabigatran, rivaroxaban, aspirin and vitamin K antagonist. Irrespective of the use of IPCD, the use of LMWH is recommended over other pharmacologic agents. LMWH should be started either 12 h before or after surgery instead of within 4 h of surgery. Dual prophylaxis (pharmacologic plus IPCD) and extending duration to 35 days are recommended in cases of major orthopaedic surgeries. In patients who are at high risk of bleeding, instead of using a pharmacologic agent, an IPCD or no prophylaxis should be used. When IPCD use is not possible (uncooperative patient/patient declines), apixaban or dabigatran should be used. There is no need to do ultrasound screening in asymptomatic patients before hospital discharge. The reader is directed to study the guidelines in detail4 and commentaries5 on them, if interested.

DOES MY PATIENT NEED ICU?

Unforeseen admission to ICU after joint arthroplasty can be a financial and logistical problem for the health care provider in addition to being an emotional burden for the family. Although perioperative and postoperative monitoring can sometimes detect the need, it is best to predict future need for ICU from preoperative and intraoperative factors. A study evaluating 22,343 arthroplasties has identified the risk factors as smoking, low haemoglobin level, higher BMI, older age (>65), higher preoperative C reactive protein, general anaesthesia, allogenic transfusion (3.5 times higher risk) and cemented arthroplasty.6

Recently described Penn Arthroplasty Risk Score7 includes five independent predictors, COPD, coronary artery disease, congestive heart failure (1 point each),...