Perioperative Management for Hepatic Resection Surgery

Metadata

Author: Jaishel Patel
Full Title: Perioperative Management for Hepatic Resection Surgery
Category: #books

Highlights

The liver parenchyma has the unique ability to regenerate via hyperplasia of the hepatocytes. This process commences within 24 h of resection with the liver typically reaching its original size by 6 months. However, complete functional recovery may occur within 23 weeks (Page 2)
The ChildTurcottePugh (CTP) system divides cirrhosis into three classes; A least severe; B moderate; C most severe. It correlates strongly with mortality after hepatectomy. Class C is considered an absolute contraindication to surgery whereas patients of Class A are generally considered good candidates for hepatic resection. Although some Class B patients may undergo resection, the risks are signiﬁcantly increased, and a limitation of the CTP system is in discriminating within this group.10 The model of end-stage liver disease (MELD) score is also used to predict perioperative risk in patients with CLD or endstage liver disease. Whilst there is no clear cut-off level for elective surgery, a score between 10 and 15 is associated with increased risk. (Page 2)
Future liver remnant of 20% is considered the minimum safe volume for patients with normal liver function, whereas 3040% is required for patients who have severe steatohepatitis or have received hepatotoxic chemotherapy. At least 50% is necessary for patients with cirrhosis.11 (Page 2)
techniques are equally effective. A balanced, multimodal, opioid-sparing approach comprising regional techniques and analgesic adjuncts is currently favoured. Considerations include: (Page 3)
Paracetamoldespite fears of hepatotoxicity, paracetamol appears to be safe in all but the most extensive resections. Risk factors for hepatotoxicity include liver disease, age, malnutrition and intraoperative liver ischaemia. (Page 3)
Several strategies have been developed to generate compensatory hypertrophy of the FLR and reduce the risk of PHLF. Techniques used currently include portal vein embolisation (PVE); portal vein ligation and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS); and liver venous deprivation (LVD). (Page 3)
NSAIDsthese are effective and opioid-sparing. They should be used if not contraindicated. (Page 3)
Intravenous opioidsreducing the use of opioids decreases the incidence of their adverse effects (e.g. PONV, respiratory depression) and promotes postoperative recovery. Despite this they remain in common use both during and after surgery. (Page 3)
Thoracic epidural analgesiawhilst a well-working epidural offers excellent analgesia, the risks of postoperative hypotension, ﬂuid overload and impaired mobility alongside reportedly high failure rates and risk of complications (such as nerve injury and epidural haematoma) has seen a move towards the use of alternative techniques. (Page 3)
Intrathecal morphine (ITM)spinal anaesthesia has a lower failure rate compared with TEA, and is often simpler and quicker to perform.15 A systematic review of 11 trials comparing ITM with other modes of analgesia in patients undergoing open hepatic surgery demonstrated equivalent or lower pain scores with ITM. Compared with TEA, ITM reduced requirements for ﬂuids and hospital stay. There was no difference in the rate of major complications.16 (Page 3)
The main tenet of anaesthesia for hepatic resection surgery is to optimise the patient’s haemodynamic status using judicious ﬂuids and vasoactive agents in order to create conditions that minimise hepatic venous blood loss whilst maintaining end-organ perfusion. (Page 3)
Continuous wound infusion (CWI) cathetersCWI catheters are an opioid-sparing alternative to TEA and may be used in conjunction with other techniques (e.g. ITM). They may be sited subcutaneously, subfascially or preperitoneally and there is debate over the optimal placement. A recent meta-analysis showed preperitoneal catheters provided superior pain relief compared with subcutaneous catheters. Evidence comparing CWI catheters with TEA in open hepatic resection is conﬂicting, although current guidelines state that when all aspects of postoperative care are optimised, CWI catheters in conjunction with a multimodal analgesic regimen offers a clinically acceptable alternative to TEA. (Page 3)
Trunk blocksthere is growing interest in the use of transversus abdominal plane (TAP) blocks and erector spinae blocks as alternatives to TEA, although more clinical evidence is needed. In living donor liver resection, TAP blocks are associated with less opioid consumption, lower pain scores and shorter length of stay (LOS).17 (Page 3)
The requirement for invasive monitoring depends upon the patient’s characteristics, size of resection, surgical approach (minimally invasive or open) and duration of the procedure. Blood loss can be sudden and catastrophic, and blood products should be readily available. Hypothermia should be avoided. (Page 3)
During parenchymal resection with hepatic inﬂow occlusion, the main source of bleeding is backﬂow from the valveless hepatic veins. Control of central and thus hepatic venous pressure is crucial to reduce blood loss, with the aim of achieving a near ‘bloodless’ ﬁeld. Various strategies aimed at decreasing central venous pressure (CVP) have been used including diuretics (furosemidealso a venodilator); vasodilator infusions (glyceryl trinitrate); opioid infusions in the placing Trendelenburg position; avoidance of PEEP (positive end(remifentanil); patient the (Page 3)
Thoracic epidural analgesia (TEA)traditionally the gold standard in open liver resectionis no longer recommended in ERAS guidelines afthe emergence of evidence suggesting alternative ter (Page 3)
expiratory pressure); and ﬂuid restriction until the parenchymal resection is complete. (Page 4)
Previous studies have demonstrated that CVP >5 cmH2O signiﬁcantly increases bleeding and although maintenance of low CVP (<5 cmH2O) intraoperatively is a well-practiced technique, its effectiveness and safety remain under scrutiny.18 A low CVP may lead to cardiovascular instability, intraoperative hypovolaemia and reduced renal and hepatosplanchnic blood ﬂow. Supplementary vasoconstrictor drugs are often required to maintain systemic perfusion pressure over vasoconstrictor-associated splanchnic hypoperfusion causing secondary hepatic ischaemia, there is no evidence to support this, nor is there deﬁnitive evidence demonstrating a link between low CVP anaesthesia and renal insufﬁciency. organs. Despite concerns other of A meta-analysis of low CVP anaesthesia in hepatic resection demonstrated a reduction in blood loss and transfusion requirements but no improvement in clinical outcomes.19 Conversely a retrospective analysis of 135 hepatic resections found the use of CVP monitoring had no effect on intraoperative blood loss.20 In minimally invasive surgery monitoring CVP is complicated by transmitted pressure from the pneumoperitoneum making targeted low CVP anaesthesia less applicable. (Page 4)
temporary hepatic Various hepatic vascular occlusion techniques have been used to reduce blood loss during surgical dissection. These inﬂow occlusion (Pringle include manoeuvre) or inﬂow and outﬂow occlusion such as total vascular exclusion (TVE). These techniques are designed to isolate hepatic circulation (inﬂow, outﬂow, or both) from the systemic circulation, thereby reducing blood loss during dissection and transection of the hepatic parenchyma. (Page 4)
The Pringle manoeuvre is an example of an inﬂow occlusion method that involves clamping the hepatoduodenal ligament to interrupt blood ﬂow in both the hepatic artery and portal vein. The subsequent decrease in venous return and increase in systemic vascular resistance may result in significant haemodynamic instability, and good communication between the surgeon and anaesthetist is essential during cases where it is being used. Prolonged continuous interruption of hepatic inﬂow (>1 h in normal liver or >30 min in pathological liver) may cause an ischaemia/reperfusion injury meaning occlusion is usually performed intermittently, allowing for 1020 min of interrupted liver blood ﬂow followed by a 5-min period of reperfusion. This protects the liver by limiting the total ischaemic time and inducing ischaemic preconditioning.21 (Page 4)
signiﬁcant blood loss can go unnoticed during CUSA usage as the suction is at the point of resection, and accumulates in separate canisters from the standard suction devices, often hidden under drapes. (Page 4)

Perioperative Management for Hepatic Resection Surgery

Metadata

Author: Jaishel Patel
Full Title: Perioperative Management for Hepatic Resection Surgery
Category: #books

Highlights

The liver parenchyma has the unique ability to regenerate via hyperplasia of the hepatocytes. This process commences within 24 h of resection with the liver typically reaching its original size by 6 months. However, complete functional recovery may occur within 23 weeks (Page 2)
The ChildTurcottePugh (CTP) system divides cirrhosis into three classes; A least severe; B moderate; C most severe. It correlates strongly with mortality after hepatectomy. Class C is considered an absolute contraindication to surgery whereas patients of Class A are generally considered good candidates for hepatic resection. Although some Class B patients may undergo resection, the risks are signiﬁcantly increased, and a limitation of the CTP system is in discriminating within this group.10 The model of end-stage liver disease (MELD) score is also used to predict perioperative risk in patients with CLD or endstage liver disease. Whilst there is no clear cut-off level for elective surgery, a score between 10 and 15 is associated with increased risk. (Page 2)
Future liver remnant of 20% is considered the minimum safe volume for patients with normal liver function, whereas 3040% is required for patients who have severe steatohepatitis or have received hepatotoxic chemotherapy. At least 50% is necessary for patients with cirrhosis.11 (Page 2)
techniques are equally effective. A balanced, multimodal, opioid-sparing approach comprising regional techniques and analgesic adjuncts is currently favoured. Considerations include: (Page 3)
Paracetamoldespite fears of hepatotoxicity, paracetamol appears to be safe in all but the most extensive resections. Risk factors for hepatotoxicity include liver disease, age, malnutrition and intraoperative liver ischaemia. (Page 3)
Several strategies have been developed to generate compensatory hypertrophy of the FLR and reduce the risk of PHLF. Techniques used currently include portal vein embolisation (PVE); portal vein ligation and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS); and liver venous deprivation (LVD). (Page 3)
NSAIDsthese are effective and opioid-sparing. They should be used if not contraindicated. (Page 3)
Intravenous opioidsreducing the use of opioids decreases the incidence of their adverse effects (e.g. PONV, respiratory depression) and promotes postoperative recovery. Despite this they remain in common use both during and after surgery. (Page 3)
Thoracic epidural analgesiawhilst a well-working epidural offers excellent analgesia, the risks of postoperative hypotension, ﬂuid overload and impaired mobility alongside reportedly high failure rates and risk of complications (such as nerve injury and epidural haematoma) has seen a move towards the use of alternative techniques. (Page 3)
Intrathecal morphine (ITM)spinal anaesthesia has a lower failure rate compared with TEA, and is often simpler and quicker to perform.15 A systematic review of 11 trials comparing ITM with other modes of analgesia in patients undergoing open hepatic surgery demonstrated equivalent or lower pain scores with ITM. Compared with TEA, ITM reduced requirements for ﬂuids and hospital stay. There was no difference in the rate of major complications.16 (Page 3)
The main tenet of anaesthesia for hepatic resection surgery is to optimise the patient’s haemodynamic status using judicious ﬂuids and vasoactive agents in order to create conditions that minimise hepatic venous blood loss whilst maintaining end-organ perfusion. (Page 3)
Continuous wound infusion (CWI) cathetersCWI catheters are an opioid-sparing alternative to TEA and may be used in conjunction with other techniques (e.g. ITM). They may be sited subcutaneously, subfascially or preperitoneally and there is debate over the optimal placement. A recent meta-analysis showed preperitoneal catheters provided superior pain relief compared with subcutaneous catheters. Evidence comparing CWI catheters with TEA in open hepatic resection is conﬂicting, although current guidelines state that when all aspects of postoperative care are optimised, CWI catheters in conjunction with a multimodal analgesic regimen offers a clinically acceptable alternative to TEA. (Page 3)
Trunk blocksthere is growing interest in the use of transversus abdominal plane (TAP) blocks and erector spinae blocks as alternatives to TEA, although more clinical evidence is needed. In living donor liver resection, TAP blocks are associated with less opioid consumption, lower pain scores and shorter length of stay (LOS).17 (Page 3)
The requirement for invasive monitoring depends upon the patient’s characteristics, size of resection, surgical approach (minimally invasive or open) and duration of the procedure. Blood loss can be sudden and catastrophic, and blood products should be readily available. Hypothermia should be avoided. (Page 3)
During parenchymal resection with hepatic inﬂow occlusion, the main source of bleeding is backﬂow from the valveless hepatic veins. Control of central and thus hepatic venous pressure is crucial to reduce blood loss, with the aim of achieving a near ‘bloodless’ ﬁeld. Various strategies aimed at decreasing central venous pressure (CVP) have been used including diuretics (furosemidealso a venodilator); vasodilator infusions (glyceryl trinitrate); opioid infusions in the placing Trendelenburg position; avoidance of PEEP (positive end(remifentanil); patient the (Page 3)
Thoracic epidural analgesia (TEA)traditionally the gold standard in open liver resectionis no longer recommended in ERAS guidelines afthe emergence of evidence suggesting alternative ter (Page 3)
Previous studies have demonstrated that CVP >5 cmH2O signiﬁcantly increases bleeding and although maintenance of low CVP (<5 cmH2O) intraoperatively is a well-practiced technique, its effectiveness and safety remain under scrutiny.18 A low CVP may lead to cardiovascular instability, intraoperative hypovolaemia and reduced renal and hepatosplanchnic blood ﬂow. Supplementary vasoconstrictor drugs are often required to maintain systemic perfusion pressure over vasoconstrictor-associated splanchnic hypoperfusion causing secondary hepatic ischaemia, there is no evidence to support this, nor is there deﬁnitive evidence demonstrating a link between low CVP anaesthesia and renal insufﬁciency. organs. Despite concerns other of A meta-analysis of low CVP anaesthesia in hepatic resection demonstrated a reduction in blood loss and transfusion requirements but no improvement in clinical outcomes.19 Conversely a retrospective analysis of 135 hepatic resections found the use of CVP monitoring had no effect on intraoperative blood loss.20 In minimally invasive surgery monitoring CVP is complicated by transmitted pressure from the pneumoperitoneum making targeted low CVP anaesthesia less applicable. (Page 4)
temporary hepatic Various hepatic vascular occlusion techniques have been used to reduce blood loss during surgical dissection. These inﬂow occlusion (Pringle include manoeuvre) or inﬂow and outﬂow occlusion such as total vascular exclusion (TVE). These techniques are designed to isolate hepatic circulation (inﬂow, outﬂow, or both) from the systemic circulation, thereby reducing blood loss during dissection and transection of the hepatic parenchyma. (Page 4)
The Pringle manoeuvre is an example of an inﬂow occlusion method that involves clamping the hepatoduodenal ligament to interrupt blood ﬂow in both the hepatic artery and portal vein. The subsequent decrease in venous return and increase in systemic vascular resistance may result in significant haemodynamic instability, and good communication between the surgeon and anaesthetist is essential during cases where it is being used. Prolonged continuous interruption of hepatic inﬂow (>1 h in normal liver or >30 min in pathological liver) may cause an ischaemia/reperfusion injury meaning occlusion is usually performed intermittently, allowing for 1020 min of interrupted liver blood ﬂow followed by a 5-min period of reperfusion. This protects the liver by limiting the total ischaemic time and inducing ischaemic preconditioning.21 (Page 4)
signiﬁcant blood loss can go unnoticed during CUSA usage as the suction is at the point of resection, and accumulates in separate canisters from the standard suction devices, often hidden under drapes. (Page 4)