Intensive Care Unit Management after Pulmonary Lobectomy

Abstract

The patients with pulmonary lobectomy invariably are shifted to the intensive care unit/high-dependency unit after the surgery because these patients can have significant minor and major complications. These complications following pulmonary lobectomy are preventable, and early identification in ICU can lead to reduced morbidity and mortality. Good intensive care management after pulmonary lobectomy can reduce the cost by decreasing the number of days patient stays in the hospital. This chapter will broadly discuss the common complications encountered in ICU after pulmonary lobectomy and approach to manage them.

1. Introduction

Lobectomy is removal of an individual lobe by ligating its contributing pulmonary artery, pulmonary vein, and lobar bronchi. Indications for pulmonary lobectomy include malignancy, to diagnose pathology of a nodule or mass, traumatic injury, broncho-pleural fistula, and bronchiectasis.

2. Surgical technique

Detailed surgical techniques are beyond the realm of this chapter and have been explained in other chapters. Broadly speaking, it is open or minimally invasive lung resection. Minimally invasive techniques have shown benefit when compared with open thoracotomy. Several systematic reviews have reported faster recovery and shorter hospital stay with minimally invasive technique [1, 2, 3, 4, 5, 6, 7]. Older patients are independent sooner with minimally invasive procedures compared with larger chest incisions despite the extent of surgery being similar internally.

3. Selection of the patients at risk after pulmonary lobectomy for ICU admission

The post-operative mortality rates after a major thoracic surgical procedure can range from 2 to 5%. The cardiopulmonary morbidity can range between 20 to 40% and this can result in prolonged hospital stay and increased cost. There are several patients related and procedure related risk factors which can indicate a high risk of postoperative complications.

The patient related risk factors include:

1. ASA (American Society of Anaesthesiologists) physical status ≥ 3

2. S-MPM (Surgical mortality probability model) ≥ 6 points

3. RCRI (Revised cardiac risk index) > 2 points

4. ThRCRI (Thoracic RCRI) >1.5 points

5. ARISCAT (Assess Respiratory Risk in Surgical patients in Catalonia risk index) > 45 points

6. Preoperative FEV1< 60%

7. Predictive-DLCO < 30%

The Procedure-related risk factors include:

1. High risk procedure

2. Major intraoperative complications like refractory hypotension, myocardial ischemia, cardiac arrhythmia, major haemorrhage, and bronchial aspiration

3. Low level of hospital and operative expertise

4. Emergency operation

It is usually advisable to shift any of the above patients to ICU for post-operative monitoring.

4. ICU management

4.1 Bronchial hygiene

While patient is intubated, regular suctioning is helpful for secretion clearance, avoid lung collapse and development of pneumonia. After extubation, chest physiotherapy, incentive spirometry and ambulation are important to promote secretion clearance.

4.2 Ventilation

Usually, patients are extubated in theatre or recovery post operatively. If they continue to be ventilated, aim is to minimize barotrauma by using low tidal volume ventilation and moderate levels of PEEP (less than 10 cm water). Significant air trapping and auto-PEEP is not uncommon in patients with emphysema. Adequate tidal volume and expiratory time and avoiding excess PEEP will help in preventing air trapping. Ventilator should be weaned as soon as possible to prevent nosocomial infection and promote patient participation in early mobilisation and physiotherapy.

In selected patients, high-flow nasal cannula oxygen therapy may be used cautiously to treat hypoxemia after extubation in the early postoperative period [8]. While not routinely used after pulmonary resection, continuous positive airway pressure (CPAP) is reasonable if otherwise indicated (e.g., obstructive sleep apnoea). In small studies, CPAP appears to improve oxygenation without increasing air leakage through the chest drain or the incidence of other postoperative complications [9, 10].

4.3 Hemodynamics and fluid management

It is important to maintain adequate intravascular volume to maintain adequate cardiac output. Fluid therapy is aimed at maintaining low or low-normal cardiac filling pressures. Restrictive fluid strategy may reduce pulmonary complications and facilitate early extubation. While the fluid regimen should be individualized to optimize cardiac output and oxygen delivery, excessive fluid administration (i.e., >3 L in the 24 hours of the perioperative period) is associated with acute lung injury and delayed recovery after open thoracic surgery [11, 12, 13, 14, 15, 16, 17]. In one study, the risk of acute lung injury increased for each 500 mL increment of perioperative fluid (odds ratio [OR] 1.17, 95% CI 1.00–1.36) [12].

Invasive cardiac monitoring is usually not needed beyond first 24 hours. In our practice, we prefer to give bolus dose of intravenous fluids rather than continuous maintenance fluid.

4.4 Vasopressors

The combination of general anaesthesia and thoracic epidural analgesia can cause hypotension. Rather than administering additional fluid to support BP in a euvolemic patient, we suggest using an infusion of a low dose of a vasopressor agent typically noradrenaline to maintain adequate Mean Arterial Pressure.

4.5 Post-operative analgesia

Thoracotomy induces severe postoperative pain which can cause respiratory complications, such as hypoxia, atelectasis, and pulmonary infections. In addition, inadequate pain control can lead to post-thoracotomy pain syndrome, which may continue for many years; therefore excellent analgesia after lung surgery is vital. This will allow deep breathing, coughing and early mobilisation.

It is well established that VATS offers the benefit of major pulmonary resection with decreased early postoperative pain, decreased need for opioid analgesia, decreased hospital stay, and faster recovery and return to preoperative activities [18, 19]. Minimally invasive lung resection confers an improved short-term quality of life and decreased chronic pain as documented in several studies [20, 21, 22, 23].

Guidelines on postoperative analgesia published by the American Society of Regional Analgesia and Pain Medicine and the American Society of Anaesthesiologists’ Committee on Regional Anaesthesia emphasise the importance of multimodal agents which work on different pain pathways and use of systemic and local-regional analgesia to support opioid-sparing strategies and reduce systemic side effects.

4.5.1 Opioids

Administration routes are multiple including intravenous, subcutaneous, and oral preparations. The most habitual way is the patient-controlled analgesia (PCA) transitioning to oral opioids once patient has resumed oral intake. Common agents for PCA are morphine, fentanyl, and oxycodone. Other common opioids are codeine and tramadol. Basal infusion of opioids, with or without PCA, must be limited in opioid-naive patients because of the increased risk of side effects, including hypotension, respiratory depression, itching, nausea, vomiting, ileus, confusion, and sedation.

4.5.2 Opioid sparing agents

With Non-steroidal anti-inflammatory drugs (NSAIDs) the use of opioids is reduced but more risk of kidney injury, gastric bleeding, and effect on platelets aggregation. In our practice, nonsteroidal drugs are usually avoided if concomitant pleurodesis is performed. Paracetamol is an acetanilide derivative which can be given both orally and intravenously. Paracetamol acts by inhibiting substance P action and central prostaglandin synthesis. N-methyl-D-aspartate (NMDA) antagonists Ketamine is another opioid sparing agent, but side effects include hallucinations and restricted mobility with continuous intravenous infusion. Gabapentinoids may help reducing neuropathic pain after thoracic surgery. Literature indicates that preoperative administration of gabapentinoids may also reduce postoperative pain and opioid usage.

4.5.3 Regional analgesia

Thoracic epidural analgesia (TEA) is considered the gold standard technique in pain management, usually recommended as first line after thoracic surgery. It provides better pain relief than opioid PCA treatment and permits a faster recovery. Local anaesthetics added to opioids in TEA increase analgesia efficacy. Major deterrent to epidural use is its invasiveness. Other side effects could be sympathetic blockade, respiratory depression, and urinary retention.

Thoracic paravertebral block (TPVB) is commonly used, especially with VATS approach. It is often proposed as an alternative to TEA because results in term of pain control are comparable to TEA, with fewer side effects. Pain in the very immediate post-operative period can be covered with a single shot of TPVB but to have a longer analgesic effect, a continuous TPVB analgesia with a catheter placed in the paravertebral space should be considered.

Intercostal nerve block is a very well-known technique, especially to treat pain after thoracotomy. Both the single-shot technique and the continuous infusion are possible with infusion more effective after thoracic surgery. The continuous infusion of local anaesthetic in the intercostal space provides pain relief comparable to TEA, until approximately the 5th postoperative days after open surgery.

Serratus anterior plane block (SAPB) is a thoracic wall nerve block that covers the lateral cutaneous branch of the intercostal nerves from T2 to T9. The SAPB provides more hemodynamic stability compared with TEA after thoracotomy and reinforces PCA analgesia reducing pain and opioid use. In patients undergoing VATS, the loco-regional techniques help in both reducing pain and opioid consumption in the first 24–48 hours after intervention.

4.6 Antibiotic prophylaxis

Postoperative antibiotic prophylaxis after lobectomy is controversial. Deguchi et al has shown that prophylactic antibiotic administration in both intraoperative and postoperative periods reduced the incidence of pneumonia after pulmonary lobectomy for non-small cell lung cancer [24]. A prospective randomized double-blind trial of flash cefuroxime versus forty-eight- hour cefuroxime in pulmonary surgery has shown the benefit of reducing the rate of deep infections and particularly the rate of empyema [25]. However, a double blind, placebo controlled, randomized trial by Oxman et al has shown not to reduce the number of infectious complications compared with preoperative prophylaxis only [26]. In our institution, 24 hours of antibiotic post operatively is usually prescribed based on local microbiologic susceptibility.

4.7 Nutrition

Early introduction of nutrition helps in recovery post operatively. Inadequate calorie and protein intake during critical illness is associated with poor clinical outcomes. Nutritional risk screening should be performed within 24–48 hours of hospital admission to identify patients at high risk of malnutrition. Nutrition Risk in the Critically Ill (NUTRIC score) and Nutritional Risk Screening 2002 (NRS 2002) have been extensively studied as screening tools. Once a patient is identified as at risk, formal nutritional assessment by a trained healthcare professional should be performed. An enteral formula with appropriate macronutrient and micronutrient composition may assist patients in meeting nutritional goals. Conventionally, enteral nutrition is encouraged to help maintain gut structure and function including that of the T-cell associated lymphoid tissues and neutrophil activation [27]. The ASPEN guidelines published recently suggest feeding between 12 and 25 kcal/kg in the first 7–10 days of ICU stay with protein intake 1.2–2 kcal/kg/day [28]. Parenteral nutrition is usually not needed in postoperative patients with pulmonary lobectomy. However, if enteral feed is not tolerated, parenteral nutrition may be considered.

4.8 Renal failure

Incidence of acute kidney injury has been reported in 6–10% patients undergoing lung resection surgery with more complicated intra-hospital course. Hence, maintain normovolemia, normal cardiac output, avoid nephrotoxic medications and monitor urine output along with renal function.

4.9 Enhanced recovery protocols

These typically incorporate aspects of preoperative, intraoperative, and postoperative care to reduce morbidity. Specific Enhanced Recovery Protocols for thoracic surgery have shown benefits in reduced opioid use, less fluid administration, decreased pulmonary and cardiac morbidity, and reduced hospital length of stay [29, 30, 31].

5. Chest tube management

Following lobectomy, one or more chest tubes are placed in the thoracic cavity. Chest tubes are typically placed through a separate incision when a thoracotomy is performed. When a minimally invasive technique is performed, chest tubes can also be placed directly through the port sites. In a trial that randomly assigned 40 patients to thoracic drainage using the same intercostal space as the thoracotomy incision or traditional chest drainage using a separate incision, the mean lengths of hospital or intensive care unit stay, pain scores, and complications (including infection) were similar between the groups [32].

Postoperative management of chest tubes is directed by postoperative imaging, presence or absence of air leak and the volume and/or character of drainage. Following both open and minimally invasive techniques, typically the chest tube is connected to suction in the immediate postoperative period for at least 12 hours, then disconnect the suction leaving the chest tube to water seal.

The decision to place a chest tube to suction versus water seal alone, if a postoperative pleural leak is present, is controversial. Multiple randomized trials have compared outcomes for patients assigned to chest tubes placed to water seal or to suction following lung resection following a brief period of suction [33, 34, 35, 36, 37, 38]. A meta-analysis that included 7 RCTs found no difference in duration of air leak, incidence of prolonged air leak, duration of chest tubes and duration of hospital stay when chest tubes were placed to suction rather than water seal [39].

Chest tubes must be evaluated multiple times every day to ensure patency of the tubes, and to assess for their on-going requirement. We leave the chest tubes in position as long as there is any air leak, or the draining fluid effluent volume is >300 mL/day.

6. Complications associated with pulmonary lobectomy in ICU

Pulmonary complications following thoracic surgery are the most common cause of morbidity followed by cardiovascular-related morbidity, and the incidence of these complications increase with increasing age. In general, complications related to minimally invasive thoracic procedures are similar to those of the open surgical approaches. Common complications following lung resection include arrhythmias, postoperative atelectasis, respiratory failure, bleeding, surgical site infection, prolonged postoperative air leak, and bronchopleural fistula.

6.1 Respiratory failure

In a secondary analysis of the American College of Surgeons Oncology Group (ACOSOG) Z0030 trial [40], the incidence of respiratory failure requiring ventilation was 3.7% and Adult Respiratory Distress Syndrome was 0.3%. Pulmonary complications such as atelectasis, bronchospasm and pneumonia can lead to respiratory failure. In a retrospective study of nearly 17,000 patients undergoing lung resection surgery, 3.5% required re-intubation. Risk factors for reintubation included age, male gender, clinically significant comorbidities (or ASA physical status ≥4), tobacco use, and prolonged duration of surgery [41].

Pulmonary oedema can be seen in 1–5% patients after pulmonary lobectomy. It is a noncardiogenic and non-infectious pulmonary oedema caused by increased permeability and diffuse alveolar damage. The treatment of this pulmonary oedema is to “keep the patient dry”, early reintubation or trial of non-invasive ventilation in cases of respiratory failure. In addition, administration of inotropic/vasopressor drugs, while restricting fluid intake as mentioned above.

6.2 Cardiac arrhythmias

Supraventricular tachyarrhythmia is more common than ventricular rhythm disturbances after noncardiac thoracic surgery. Atrial fibrillation (AF) is the most common arrhythmia occurring in 10–20% of patients after lobectomy and occurs most commonly in first four days postoperatively. Risk factors for AF after lung cancer surgery are increasing age, increasing extent of operation, male sex, non-black race and stage II or greater tumour [42].

Extensive guidelines are available from the American Association for Thoracic Surgery [43]. There are some prevention strategies which help reduce the postoperative atrial fibrillation. These strategies include correction of magnesium when abnormal and also avoiding beta-blockade withdrawal for those chronically on these medications. It may be reasonable to administer diltiazem to patients with preserved cardiac function who are not on beta blockers preoperatively or to give post-operative amiodarone to reduce incidence of post-operative AF. Simple treatment strategies to control AF includes the optimization of fluid balance, correct electrolytes and treat triggering factors (bleeding, pulmonary embolism, pneumothorax, pericardial processes, airway issues, myocardial ischemia, or infection). For hemodynamically unstable patient with the new onset post-operative AF of less than 48 hours duration, emergency DC cardioversion is indicated. For hemodynamically stable patient, rate control strategy is reasonable. Agents commonly used are beta blockers, non-dihydropyridine calcium channel blockers or digoxin. Rhythm control with antiarrhythmic drugs and/or DC cardioversion can be useful for patients with hemodynamically stable new onset AF who have recurrent or refractory AF, continued symptoms, intolerance to rate control medications, or ventricular rates that cannot be adequately controlled. For rhythm control, amiodarone is the most common drug used. Other agents which can be used are sotalol and flecainide.

6.3 Haemorrhage

Post lobectomy haemorrhage is rare but most common indication for reoperation. In a recent single centre retrospective review [44], out of 1960 lobectomies, haemorrhage occurred in 2.1% cases, leading to reoperation in 1.4% and non-operative management in 0.8% cases. The median time for reoperation was 17 hours.

6.4 Postoperative leak

Persistent postoperative air leak, defined arbitrarily as pulmonary leak of more than seven days, occurs in 10–15% of patients following lobectomy. Persistent air leaks are more common in patients with severe COPD. Management is often conservative with on-going chest tube drainage or home discharge with one way flutter valve. Most air leaks seal within two weeks with conservative care. Postoperatively, patients should be extubated as soon as possible to reduce intrapulmonary pressure. Other treatments including injection of talc, other sclerosing agents and autologous blood may be helpful to close a persisting air leak. In more difficult cases, intrabronchial valves have been proposed to close alveolar pleural fistulas.

6.5 Bronchopleural fistula

Bronchopleural fistula, which is a direct communication of the bronchus and the pleural space, is a major complication of lung resection and occurs in 1–2% of lobectomies. Management requires reoperation for bronchial closure, pleural space drainage, and sterilization.

6.6 Injury to the organs

Injury to the diaphragm, liver, or spleen may occur, particularly during port placement with consequent morbidity.

7. Conclusion

ICU management of patients with pulmonary lobectomy is required for two main reasons: post-operative setting or acute complications following surgery. Careful pre-operative assessment of patients is mandatory to reduce post-operative morbidity and mortality. The requirement of ICU depends upon the patient and on local specifics. Several cardiac and respiratory complications can happen in ICU following admission after pulmonary lobectomy. Prevention and early recognition, as well as interdisciplinary cooperation are essential to obtain the best patient centred outcome.