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Goal-Directed Fluid Therapy, Perioperative Pain Management, and Enhanced Recovery


Key Points

  • 1.

    The costs of healthcare are escalating. Goal-directed fluid therapy (GDT) and multimodal pain relief are ways to control cost while improving quality.

  • 2.

    GDT is an integral part of enhanced recovery programs (ERPs), as is multimodal pain management.

  • 3.

    The traditional, liberal approach to perioperative fluid management has no sound evidence base and causes perioperative fluid and salt overload. “Zero fluid balance” is recommended using a goal-directed approach. ERPs emphasize avoidance of salt and water overload.

  • 4.

    GDT involves cardiovascular monitoring such as minimally invasive cardiac output and application of an algorithm or guidelines specific to fluid and hemodynamic management.

  • 5.

    GDT and ERPs increase quality by decreasing variability in practice with evidence-based management. Decreased cost results from less perioperative morbidity and streamlined care delivery.

  • 6.

    Various monitors may be used for GDT, ranging from invasive (e.g., pulmonary artery catheter) to noninvasive (e.g., finger cuff cardiac output). The choice of monitor is based on the clinical situation and individual or institutional preference. The most common monitors used are esophageal Doppler and arterial pulse-wave analysis systems.

  • 7.

    ERPs are multidisciplinary, multifactorial care pathways. They incorporate optimal preoperative preparation, careful intraoperative management of fluid status and temperature, antibiotic administration, minimally invasive surgery, multimodal pain relief, postoperative nausea and vomiting control, and early mobilization.

  • 8.

    Multimodal perioperative pain relief using opiate-sparing techniques facilitates early mobilization and patient comfort and decreases opiate-related complications. Effective multimodal pain management is essential for ERPs.

With recent advances in expensive diagnostic and treatment modalities, the costs of healthcare have skyrocketed. The need to care for increasing numbers of patients undergoing procedures while controlling cost has pushed healthcare systems to devise increasingly efficient ways to deliver care. The “throughput” of patients is often stymied by prolonged hospital stays and readmission after procedures. Inefficient systems, inconsistent care, and perioperative complications cause delays, poor patient and provider satisfaction, and high cost.

Goal-directed fluid therapy (GDT), enhanced recovery programs (ERPs), and the perioperative surgical home (PSH) are three related approaches to patient care that have emerged to provide optimal outcomes for patients undergoing surgery. GDT refers to fluid and hemodynamic management targeting optimal cardiovascular performance using monitoring beyond standard noninvasive monitors. ERPs are designed to incorporate patient management processes, such as preoperative optimization, multimodal pain management, and early mobilization after surgery, so as to facilitate recovery. PSH is a construct consisting of a coordinated, multidisciplinary team using best-evidence guidelines and protocols to guide patients through the entire perioperative experience as seamlessly as possible. Fig. 19.1 shows GDT as a component of ERPs and both under the PSH umbrella. GDT and multimodal pain relief are two approaches that facilitate early ambulation, patient comfort, and enhanced recovery. These approaches are particularly important in patients with cardiovascular illness.

Fig. 19.1
Goal-directed fluid therapy (GDT) is part of enhanced recovery programs, which lie under the perioperative surgical home umbrella.

Goal-Directed Fluid Therapy

Traditional, liberal fluid management, which entailed a cookbook-type approach, is now outmoded. This involved calculation of maintenance fluid requirement based on body weight, calculation of a deficit based on the period during which the patient has not had any fluid (e.g., nothing by mouth [NPO]), presumed effects of a bowel prep, and estimation of third-space losses based on the invasiveness of the surgery. Typically, for major abdominal surgery, 6, 8, 10, or even 12 mL/kg per hour of crystalloid would be administered to replace insensible losses and loss to the third space. The concept of a “third space” has been called into question. What has been referred to as fluid loss to the third space likely represents translocation of administered fluid out of the vascular space, resulting in intracellular and extracellular edema.

Excess salt and fluid in the perioperative period is potentially harmful. Fluid and salt excess can lead to airway edema, increased lung water, tissue edema, and cardiac failure. Relative fluid restriction results in shorter hospital lengths of stay, improved wound healing, fewer surgical infections, and fewer cardiovascular and pulmonary complications. It is sometimes argued that excess perioperative fluid and salt are acceptable because, with time, the patient will mobilize the fluid. However, the potential airway problems, prolonged ventilation, increased complication rate, and extra time in recovery associated with excess fluid and salt administration are neither necessary nor acceptable. Avoidance of fluid and salt overload in major surgery is now a standard component of ERPs ( Fig. 19.2 ).

Fig. 19.2, Major components of enhanced recovery programs. CHO, Carbohydrate; NG, nasogastric; NSAIDs, nonsteroidal antiinflammatory drugs.

Overaggressive fluid restriction can have negative consequences as well, with hypovolemia leading to hypotension, tachycardia, organ ischemia, and vital organ failure. Morbidity rates are higher in the setting of either hypovolemia or hypervolemia ( Fig. 19.3 ). Targeting no perioperative change in body weight, fluid restriction protocols do allow modest fluid administration with a background rate (e.g., 1–4 mL/kg per hour) and fluid boluses to maintain hemodynamic stability. Likewise, blood products are used as needed to maintain adequate hemoglobin concentration and coagulation.

Fig. 19.3, Either hypervolemia or hypovolemia may cause impaired tissue perfusion and poor outcome.

A goal-directed, protocol-based approach to fluid and hemodynamic management has grown out of accumulating evidence that optimizing hemodynamic status improves outcome and that accurate assessment of volume and hemodynamic status using only standard, noninvasive monitors is often impossible. Tachycardia, hypotension, and oliguria can result from either hypovolemia or hypervolemia (i.e., heart failure). GDT adoption has also resulted from recognition that decreasing variability of practice using a best-evidence approach improves outcome. Decreasing process variability is essential to creating high-performance systems.

Some perioperative GDT grows out of current approaches to critically ill patients. Early, aggressive fluid and hemodynamic management of septic patients is an integral factor leading to dramatic improvements in mortality rate. This work, published in 2001, revolutionized the initial management of patients with sepsis, such that the vast majority of tertiary care centers now have a sepsis protocol that incorporates an early, goal-directed approach.

In 2002, Gan and colleagues studied 100 patients undergoing major elective surgery, randomly assigning them to receive either “standard” therapy or GDT based on esophageal Doppler parameters. The GDT group experienced shorter hospital stays (5 ± 3 days vs. 7 ± 3 days), less nausea and vomiting, and earlier return of bowel function. Numerous studies of a wide variety of surgical populations using various GDT algorithms and monitors followed, with the vast majority showing benefit. Large meta-analyses have subsequently confirmed the benefits of using thoughtful, informed fluid administration, often with the use of algorithms with sound bases in physiology.

Goal-Directed Fluid Therapy and Cost Reduction

With its decreased morbidity and hospital length of stay, GDT reduces cost. Perioperative complications, in addition to being distressing to patients and healthcare delivery teams, dramatically increase healthcare costs. This increased cost results from increased utilization of expensive resources (e.g., intensive care unit and hospital beds, diagnostic tests, medical and surgical therapies) and lost opportunity as fewer patients can be cared for in the system. A single complication in a major surgery patient can cost many thousands of dollars, and by decreasing the incidence of such complications, GDT dramatically reduces cost. The mortality rate, hospital length of stay, and direct costs for patients with at least one complication versus those with no complications are shown in Table 19.1 .

Table 19.1
Mortality Rate, Hospital Length of Stay (LOS), and Direct Costs of Patients With No Surgical Complications vs. Those With ≥1 Complication
Modified from Manecke GR, Asemota A, Michard F. Tackling the economic burden of postsurgical complications: would perioperative goal-directed fluid therapy help? Crit Care . 2014;18:566.
No Complications ≥1 Complication P Value
Mortality rate 1.4% 12.4% <.001
Hospital LOS (days) 8.1 ± 7.1 days 20.5 ± 20.1 days <.001
Direct costs (mean) $17,408 ± $15,612 $47,284 ± $49,170 <.001

Monitoring for Goal-Directed Fluid Therapy

Various monitors have been used successfully in GDT, ranging from invasive (e.g., pulmonary artery catheter) to noninvasive (e.g., finger plethysmographic waveform). The data provided supplements standard monitoring (i.e., heart rate and blood pressure) with parameters tracking overall cardiac performance such as cardiac output and stroke volume (SV), or indexes of potential fluid responsiveness such as stroke volume variation (SVV), pulse pressure variation (PPV, arterial pulse-wave analysis systems), and corrected flow time (FTc, esophageal Doppler). Continuous monitoring of central venous oxygenation also has been used to assess adequacy of circulation. Assessment of tissue perfusion by means of gastric tonometry has been used in GDT, and attempts at evaluating tissue oxygenation (e.g., near-infrared spectroscopy) have been made as well.

Each monitoring system has strengths and weaknesses, and monitoring should be tailored to individual situations and institutional preference. Although the accuracy of minimally invasive cardiac output monitors such as arterial waveform systems and esophageal Doppler has been questioned, the ability of the systems to assess and trend cardiovascular performance appears to be adequate for perioperative GDT. In critically ill or unstable patients, invasive monitors such as pulmonary artery catheters and transesophageal echocardiography should be considered. Monitors used for GDT are presented in Table 19.2 .

Table 19.2
Monitors for Goal-Directed Fluid Therapy (GDT)
Invasiveness Technology Device Parameters for GDT Strengths Weaknesses
Invasive Thermodilution, CO, pulmonary artery and central pressure Pulmonary artery catheter CO Clinical gold standard CO measurement; vast amount of potentially useful data, including RV function Invasive, requires central venous access
Transpulmonary thermodilution PiCCO (Pulsion Medical Systems) central arterial catheter Pulmonary artery and central venous pressure Vast amount of potentially useful data, including thoracic blood volume and extravascular lung water Invasive; requires central arterial access
Fiberoptic oximetry Precep Catheter (Edwards Lifesciences) Mixed venous and venous oxygen saturation Assessment of global oxygen balance and extraction ratio No direct information about cardiac performance or fluid responsiveness
Minimally invasive Doppler flow measurement, descending aorta CardioQ (Deltex Medical) CO Most common monitor successfully used for GDT Requires skill (placement)
Corrected flow time (preload, afterload), peak velocity Newer systems incorporate arterial pressure wave Inaccurate in aortic crossclamping, aortic aneurysm, aortic regurgitation
Pressure wave pulsatility Vigileo/FloTrac (Edwards Lifesciences) CO, SVV (fluid responsiveness) Easy to use SVV is a powerful parameter combined with CO Inaccurate in aortic crossclamping, aortic regurgitation, cirrhosis, and sepsis
Noninvasive Finger cuff Clearsight (Edwards Lifesciences) CO, SVV (fluid responsiveness) Noninvasive Potential accuracy issues; relatively unstudied in GDT
Finger plethysmography Pulse oximetry (Masimo) Waveform variation, pleth variability index Noninvasive Potential accuracy issues; relatively unstudied in GDT; no CO data
Thoracic electrical impedance, bioreactance, velocimetry NICOM (Cheetah Medical), ICON (Cardiotronics) CO Noninvasive Potential accuracy issues; relatively unstudied in GDT
CO, Cardiac output; RV, right ventricular; SVV, stroke volume variation.

The most studied monitor for GDT is esophageal Doppler (CardioQ Deltex Medical). This system consists of a small probe placed in the esophagus that insonates the descending thoracic aorta. Estimation of the cross-sectional area of the aorta is made based on patient characteristics (e.g., age, height, gender, and weight) and the area under the velocity time is calculated, with the terms velocity time integral (VTI) and stroke distance (SD) used interchangeably. SD is multiplied by the aortic cross-sectional area to obtain SV:


SV = SD × Aortic cross-sectional area

Because of its common use and its track record of utility in GDT, a number of algorithms have been developed for use with esophageal Doppler. These may use SV and FTc for volume responsiveness and afterload. Other potentially useful parameters include peak velocity and mean acceleration (contractility assessment) ( Fig. 19.4 ). Experienced users are able to recognize waveform changes that reflect changes in hemodynamics ( Fig. 19.5 ). Newer esophageal Doppler systems can incorporate arterial pressure waveform analysis when an arterial catheter is used, allowing the added assessment of SVV and PPV. Proper placement and use of the esophageal Doppler require practice, particularly in optimizing the velocity-time waveform. About 15 practice sessions are required to gain facility.

Fig. 19.4, Esophageal Doppler velocity-time waveform. FTc, Corrected flow time; MA, mean acceleration; PV, peak velocity; SD, stroke distance.

Fig. 19.5, Visual waveform inspection reveals a positive response to a fluid bolus, with increases in peak velocity (PV), corrected flow time (FTc), and stroke distance (SD).

The FloTrac/Vigileo system is the most commonly used arterial pressure–based system used for GDT. An arterial catheter is required, and the arterial wave is digitized by a proprietary transducer. The SV is determined by the pulsatility of the wave (standard deviation of the arterial wave), and a resistance-compliance factor, K, is calculated using patient characteristics and characteristics of the waveform:


SV = K × Pulsatility

A list of potential monitors for GDT is presented in Table 19.2 .

Noninvasive cardiac output monitoring systems are available that use pressure waveform analysis from either the finger or the wrist. They are very promising in concept because they do not involve intravascular catheters or esophageal probes. Electrical impedance and cardiometry devices are available as well. Their use for GDT has yet to be firmly established, but it is likely that they will undergo further development, becoming valuable tools.

In certain situations, particularly in critically ill patients, minimally invasive systems are inadequate to provide the detailed information that invasive ones such as pulmonary artery catheterization with thermodilution, transpulmonary thermodilution, and transesophageal echocardiography can provide. These advanced monitors provide the necessary information for GDT and allow for complex hemodynamic and cardiac problem solving as well.

Patient Selection for Goal-Directed Fluid Therapy

Goal-directed fluid therapy is recommended for major procedures in which substantial blood loss or fluid shifts are anticipated ( Box 19.1 ). These may include major general, vascular, urologic, or orthopedic surgery (e.g., pancreatectomy, open colectomy, radical cystectomy). Major patient comorbidities such as cardiac disease or a debilitated state should prompt the use of GDT as well. Many patients with cardiac disease are sensitive to fluid administration (e.g., patients with diastolic dysfunction), so use of specific guidelines for fluid administration that are based on physiologic parameters is beneficial for them. GDT has been studied in cardiac surgery with some positive results. Cardiac anesthesiologists and surgeons apply goals, hemodynamic monitoring, and interventions in managing their patients perioperatively. However, GDT, as discussed here, has not been widely adopted in cardiac surgery.

Box 19.1
High-Risk Surgeries in Which Goal-Directed Fluid Therapy Is Recommended

  • Exploratory laparotomy

  • Large bowel resection, colectomy

  • Whipple pancreato-duodenectomy

  • Hepatectomy

  • Splenectomy

  • Kidney transplant

  • Radical neck dissection

  • Aortofemoral, popliteal, or axillary bypass

  • Open hysterectomy, total abdominal or bilateral salpingo-oophorectomy

  • Hyperthermic or interperitoneal chemotherapy

  • Laminectomy fusion with instrumentation (more than three levels)

  • Arthroplasty of the hip, knee, or elbow

  • Burn excision

  • Cystoprostatectomy with ileal conduit

  • Radical cystectomy

Algorithms in Goal-Directed Fluid Therapy

Numerous algorithms have been used successfully in GDT, with application of SV and preload responsiveness parameters such as PPV, SVV, and FTc. An algorithm based solely on the patient's SV response to fluid bolus is attractive because of its simplicity ( Fig. 19.6 ), but it can be associated with fluid overload. Algorithms based solely on SVV have been used, but application of SVV as a primary parameter are limited to patients without significant arrhythmias receiving controlled positive-pressure ventilation. Likewise, Doppler FTc has been used as a preload responsiveness parameter. A synthesis of the above approaches, with use of blood pressure as an additional parameter to facilitate hemodynamic problem solving is available ( Fig. 19.7 ).

Fig. 19.6, A simple goal-directed fluid therapy algorithm based on responses to fluid bolus. SV, Stroke volume.

Fig. 19.7, Goal-directed fluid therapy algorithm used at the University of California, San Diego. Stroke volume index (SVI) is the primary parameter, and the values of the targets can be adjusted according to clinical circumstances. Corrected flow time (FTc) can be substituted for stroke volume variation (SVV) for esophageal Doppler use, and an algorithm for use when SVV or FTc cannot be applied is available as well. BP, Blood pressure; HTN, hypertension; PPV, pulse pressure variation; Pulm, pulmonary; RV, right ventricular; TV, tidal volume; Vent, ventilation; WNL, within normal limits.

A physiologic approach to GDT and hemodynamic problem solving can be achieved using a four-quadrant plot of blood flow ( x -axis) versus blood pressure ( y -axis), with chosen target hemodynamics in the center of the plot. Deviations from the target zone, depending on the quadrant, are associated with a differential diagnosis and recommended management. This approach facilitates understanding of the hemodynamics, leading to accurate, prompt diagnosis and management ( Fig. 19.8 ).

Fig. 19.8, A four-quadrant plot can be created by plotting the stroke volume index (SVI) on the x -axis and mean arterial pressure on the y -axis. A target zone (green) can be created, and deviations from the target zone are associated with hemodynamic aberrations specific to each quadrant. Point-of-care guidance for each quadrant can be provided. BP, Blood pressure; HoTN, hypotension; HTN, hypertension.

Most important, using a logical, physiologically based algorithm in a thoughtful way results in improved outcomes. The choice of algorithm depends on the monitors available, the clinical situation, and institutional preferences. Using a systematic approach to fluid and hemodynamic management with particular emphasis on avoiding fluid and salt overload results in improved outcome and with enhanced recovery for patients undergoing major noncardiac surgery ( Box 19.2 ).

Box 19.2
Goal-Directed Fluid Therapy

  • Standardizes fluid and hemodynamic management

  • Aims to avoid fluid and salt overload while avoiding hypovolemia

  • Is based on parameters beyond heart rate and blood pressure, such as

    • Minimally invasive or invasive cardiac output

    • Stroke volume variation

    • Pulse pressure variation

    • Doppler-corrected flow time

    • Central venous oxygen saturation

Many algorithms have been used successfully. The algorithm should have physiologic basis and be easy to use.

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