INTRODUCTION — Preoperative prehabilitation programs emphasize nutritional supplementation, smoking cessation, physical and cognitive exercise, and stress reduction to improve postoperative functional status and outcomes. In some cases, elective surgery may be delayed to optimize the patient’s preoperative condition. This topic discusses prehabilitation protocols including specific preoperative interventions, patient selection, timing, and outcomes after patient participation in such protocols.
Other anesthetic and surgical interventions that may be employed throughout the perioperative period to enhance recovery after certain types of surgery are addressed in separate topics:
DEFINITION AND OUTCOMES
Definition and scope of prehabilitation programs — Prehabilitation involves preoperative processes to enhance a patient’s functional capacity and optimize recovery from the stress of surgery and anesthesia. "NEW" prehabilitation programs address Nutrition, Exercise (both physical and cognitive), and Worry (stress reduction) . For current smokers, another critically important aspect of a prehabilitation program is smoking cessation . These interventions involve patient effort and behavior modification during the preoperative period. The need for surgery is considered to be a "teachable moment" that might serve as a driver for permanent behavioral changes to improve health .
While some prehabilitation protocols have focused on a single issue, "multimodal" approaches employing two or more preoperative interventions are likely optimal for most patients [4-7]. Selection criteria for participation in a prehabilitation program and decisions to delay elective surgery during attempts to improve functional capacity are patient- and procedure-specific, although specific criteria vary among institutions (see 'Patient-related factors' below and 'Selected surgical procedures' below). Institution-specific protocols also dictate management of the prehabilitation process and may be the purview of surgical, anesthesiology, oncology, and/or primary care services. Perceived challenges to broad adoption of prehabilitation programs for a wide range of surgical procedures include the resources (financial and personnel) and multidisciplinary cooperation that are necessary to implement such programs. Some centers have implemented a multidisciplinary team approach to prehabilitation and enhanced recovery programs [8-11]. (See "Enhanced recovery after colorectal surgery" and "Anesthetic management for enhanced recovery after major noncardiac surgery (ERAS)".)
Prehabilitation requires patient effort, unlike clinical interventions, to optimally manage medical conditions such as initiation or adjustment of medications to decrease blood pressure or control glucose levels . It is particularly important to identify and appropriately treat iron deficiency anemia (as soon as the decision is made to pursue surgery or at least four weeks before the scheduled date of the procedure (algorithm 1)), whether or not prehabilitation protocols are initiated during the preoperative time period. (See "Perioperative blood management: Strategies to minimize transfusions", section on 'Treatment of anemia'.)
Although four or more weeks is generally considered to be sufficient time for prehabilitation efforts, a longer period may be optimal for patients who are older and/or frail [13,14]. Also, this duration is individualized according to the patient’s diagnosis and the urgency of the planned surgical procedure [15-17].
Outcome data and limitations
●Outcome data – Patient-specific, procedure-specific, and intervention-specific studies of prehabilitation efforts are presented in the sections below. Large studies of multimodal prehabilitation efforts have noted the following results:
•In a 2022 umbrella review of 55 systematic reviews, improvements in functional recovery were noted in patients undergoing cancer surgery (moderate certainty evidence) . Some of these systematic reviews reported that various types of prehabilitation programs improved incidence of postoperative complications and/or hospital length of stay (LOS) after cardiothoracic, cancer, or other major noncardiac surgical procedures, but evidence of certainty was low to very low .
•A 2019 statewide review of 523 Medicare claims in Michigan for various types of major noncardiac surgery noted that participation in a multimodal prehabilitation program that included a home-based walking protocol, education regarding nutrition, smoking cessation, and psychological preparation shortened median hospital LOS (6 [range 4-7] versus 7 [range 4-10] days) and increased likelihood of discharge to home rather than to another facility (65.6 versus 57 percent) compared with no participation .
●Limitations – Data supporting development of prehabilitation programs are limited by heterogeneity among studies due to small size and lack of randomized controlled trial design in most, as well as variability in outcome endpoints, differences in types of surgical procedures and clinical settings (eg, unsupervised home-based interventions, supervised clinic visits), criteria for patient selection, which specific prehabilitation intervention(s) were employed, and the duration, frequency, and intensity of these intervention(s) [13,18,20,21]. Assessment of the impact of prehabilitation programs on clinically important outcomes such as perioperative complications, hospital LOS, unanticipated readmission, short- and long-term impairments, and ability to participate in planned postsurgical treatments has been challenging due to these factors .
TARGET PATIENT POPULATIONS — Although some centers offer prehabilitation programs for all surgical patients, most focus on use of resources for patients at high risk for postoperative morbidity and due to patient- and procedure-related factors.
Patient-related factors — Older age (typically ≥65 years) and documented frailty are the most common factors for patient selection for prehabilitation efforts before major surgical procedures.
Older age — Elective surgery may be postponed in older patients undergoing selected surgical procedures (see 'Selected surgical procedures' below) in order to improve preoperative functional capacity [13,14]. However, evidence regarding the impact of unimodal or multimodal prehabilitation programs on clinical outcomes is scant [14,20,22,23]. (See "Anesthesia for the older adult", section on 'Preanesthesia consultation'.)
Frailty — Similarly, elective surgery may be postponed during prehabilitation efforts in frail patients undergoing selected surgical procedures (see 'Selected surgical procedures' below) [20,22,24-30]. Notably, a longer preoperative duration may be required for prehabilitation interventions in frail patients . However, evidence is scant regarding the impact of unimodal or multimodal programs on clinical outcomes in frail surgical patients [24,31,32]. (See "Frailty".)
Frailty is associated with increased mortality, postoperative complications, hospital length of stay (LOS), discharge to institutional care, functional decline, and lower quality of life (QOL) after various types of surgical procedures [33,34]. For example, frailty is present in a high percentage of patients undergoing cardiac surgery (33 to 47 percent) and is considered to be a more relevant predictor of postoperative mortality, morbidity, and inferior health-related QOL than chronological age alone [25-29,35]. Ideal implementation of prehabilitation programs would include individualized strategies for an otherwise healthy 60-year-old adult compared with a frail 80 year old patient [4,8,10,20,22,36].
Although a simple preoperative screening test such as measurement of gait speed may help identify patients at increased risk, various assessment tools are available. However, few frailty assessment instruments have been validated for surgical patients, which has contributed to heterogeneity among studies of the impact of prehabilitation . (See "Frailty", section on 'Instruments developed to identify frailty' and "Frailty", section on 'Rapid screening tools'.)
Selected surgical procedures — Multimodal prehabilitation has primarily focused on major gastrointestinal, thoracic, urologic, and gynecologic surgical procedures for treatment of cancer, as well as on cardiac surgery.
●Major gastrointestinal or esophageal surgery – In our institution, we employ a multimodal prehabilitation program for patients undergoing major gastrointestinal tract procedures for cancer or other indications.
In a 2019 meta-analysis that included 202 patients (two randomized controlled trials and one cohort study) undergoing colorectal cancer surgery, those participating in multimodal prehabilitation that included exercise and nutritional interventions noted improved disease-free survival five years after colorectal cancer surgery (hazard ratio [HR] 0.45, 95% CI 0.21-0.93; 202 total patients) compared with those who did not participate . However, postoperative complications were similar in the two groups. A subsequent 2020 prospective study in 418 older frail colorectal cancer surgery patients (see 'Patient-related factors' above) also noted that prehabilitation had little effect on postoperative outcomes . Similar results were noted in several retrospective studies of prehabilitation efforts [39,40].
However, results are inconsistent for major abdominal surgery. Some smaller studies have noted fewer postoperative complications and cost savings over $20,000 , fewer 30-day hospital readmissions , decreased incidence of delirium , increased likelihood of recovery of baseline functional capacity at four postoperative weeks , or longer postoperative six-minute walking test (6MWT) distances at four and eight postoperative weeks  in patients participating in multimodal prehabilitation protocols compared with controls.
For patients undergoing esophageal surgery for cancer resection, a 2018 randomized trial in 68 patients noted that prehabilitation (nutrition and physical exercise) improved postoperative functional capacity measured with the 6MWT (mean change +15.4 ± 65.6 versus -81.8 ± 87.0 meters) .
●Urologic surgery – We also employ our prehabilitation program for patients undergoing major urological surgical procedures. In a 2021 randomized trial of 70 males undergoing radical cystectomy, a prehabilitation program that included aerobic and resistance exercise, nutrition, and relaxation techniques resulted in improved functional capacity measured with the 6MWT (mean change +40.8 ± 114.0 versus +9.7 ± 108.4 meters) meters) four weeks after surgery .
●Gynecologic surgery – We also employ our prehabilitation program for major gynecologic surgery. Outcome studies noting improvements in physical and psychologic parameters, complication rates, as well as shorter length of stay are discussed in a separate topic. (See "Enhanced recovery after gynecologic surgery: Components and implementation", section on 'Health status optimization'.)
●Thoracic surgery – Many institutions employ prehabilitation for patients undergoing lung cancer resection.
A 2020 randomized trial in 73 patients undergoing thoracoscopic lobectomy for lung cancer noted improved perioperative functional capacity after a two-week home-based multimodal prehabilitation program that included nutrition counseling, aerobic and resistance exercises, respiratory training, and psychological guidance, compared with standard preoperative care . Specifically, forced vital capacity was 0.35 L higher (95% CI 0.05-0.66) and the 6MWT was 60.9 m longer (95% CI 32.4-89.5) in patients receiving prehabilitation.
Other studies of unimodal prehabilitation before thoracic surgery have focused on physical exercise and respiratory muscle training, as discussed below. (See 'Physical exercise programs' below.)
●Cardiac surgery – Many institutions follow guidelines established for cardiac surgical patients who may benefit from prehabilitation programs, including those who are frail, have cognitive dysfunction, or need for smoking cessation identified during the preoperative consultation [4,35,48]. The importance of nutrition support is particularly emphasized (see 'Nutritional supplementation' below) [49-51]. Notably, preoperative vitamin D deficiency is associated with postoperative delirium in cardiac surgical patients .
One 2019 network meta-analyses of four meta-analyses concluded that multimodal prehabilitation efforts reduce postoperative pulmonary complications and hospital LOS in cardiac surgical patients . Evidence of benefit was strongest for inspiratory muscle training.
SPECIFIC INTERVENTIONS — Multimodal approaches to prehabilitation that employ two or more preoperative interventions are optimal for most patients [4-7]. Descriptions and outcomes for specific components of prehabilitation programs are discussed below.
Nutritional supplementation — Malnutrition is common in patients undergoing major surgical procedures. Preoperative assessment of nutritional status (figure 1) and interventions to treat malnutrition are addressed in separate topics:
Regardless of assessment results, these authors recommend oral protein supplementation and immunomodulation nutrition five to seven days before surgery for all patients, and more aggressive interventions for a longer duration for malnourished patients.
Smoking cessation — Strong encouragement to cease smoking is often part of a prehabilitation program. Cessation for four to eight weeks before surgery is ideal to minimize risk of postoperative pulmonary complications. Details regarding perioperative risks of smoking, benefits of cessation, and specific behavioral interventions and pharmacotherapy to aid with cessation are discussed separately:
Physical exercise programs
●Identification of poor functional capacity – Low anaerobic threshold is associated with perioperative mortality [54-56]. We screen high-risk patients undergoing major abdominal or cardiothoracic surgery for poor functional capacity based on the following risk factors:
•Frailty (see 'Frailty' above)
•Poorly controlled chronic illnesses (eg, diabetes or hypertension)
•Preoperative chemotherapy or radiation therapy
•Inactivity by WHO standard (<150 minutes of moderate intensity or <75 minutes of vigorous intensity exercise per week)
Patients who meet one or more of these criteria would benefit from physical exercise programs as a part of their prehabilitation .
Additionally, we use assessments of functional capacity that include:
•Gait speed. In one prospective cohort study of more than 15,000 cardiac surgical patients ≥60 years of age, gait speed was an independent predictor of adverse outcomes; an 11 percent relative increase in mortality was noted for each 0.1 m/sec decrease in speed .
•Time to complete five chair sit-to-stand repetitions .
•Dominant handgrip strength (average of three measurements) .
•Quadriceps femoris thickness measured by ultrasound .
Other assessments include:
•Stair-climbing test .
•Shuttle walk test .
•Six-minute walking test (6MWT) distance to assess aerobic capacity and endurance by measuring the distance traveled by the patient while walking for six minutes [64,65]. This test has been used in studies to compare baseline versus post-intervention changes. Unfit patients with poor baseline walking capacity are most likely to improve with prehabilitation that includes physical exercise .
•Cardiopulmonary exercise testing (CPET), which indicates the transition from aerobic metabolism to anaerobic metabolism (ie, the anaerobic threshold) [67,68]. However, CPET can be time- and resource-consuming.
●Interventions to improve physical function – Some prehabilitation programs include preoperative physical exercise for sedentary patients with poor functional capacity [7,66,69]. Training programs may include aerobic, resistance, flexibility, balance, and strength exercises, as well as inspiratory muscle training (IMT) [13,57,69]. Inclusion of IMT in the exercise program may be particularly important for patients with obesity , chronic obstructive pulmonary disease [71,72], or those undergoing major upper abdominal, cardiothoracic, or cancer surgical procedures [36,47,53,72-80]. Typically, these interventions are implemented in a supervised setting; however, some centers use home-based interventions .
Systematic reviews of the efficacy of preoperative physical exercise and/or respiratory training after major abdominal, thoracic, and cardiovascular surgical procedures have reported inconsistent results as well as substantial heterogeneity among studies:
•Major abdominal surgery – A 2020 systematic review of preoperative exercise programs (aerobic together with resistance training, IMT, coughing, or stretching) before major liver, colorectal, gastroesophageal, or general abdominal surgery that included eight randomized trials with 442 patients noted a significant reduction in overall morbidity (OR 0.52, 95% CI 0.30 to 0.88) and postoperative pulmonary complications (PPCs) (odds ratio [OR] 0.37, 95% CI 0.20 to 0.67) compared with standard care . Other systematic reviews in patients undergoing major abdominal surgery have also noted reduction in PPCs [21,80-84].
•Thoracic surgery – A 2022 systematic review reported postoperative outcomes after preoperative exercise training that included supervised or unsupervised aerobic, resistance, IMT or any combination of these types of training before open or video-assisted resection of non-small cell lung cancer (636 participants; 10 randomized trials) . The investigators noted reduced risk of developing PPCs (risk ratio [RR] 0.45 95%CI 0.33-0.61) and reduced postoperative length of stay (LOS) in the hospital (–2.24 days, 95% CI -3.64 to –0.85 days). Exercise training also improved preoperative exercise capacity (measured by peak oxygen consumption), but had little or no effect on lung function (measured by forced expiratory volume in one second). Similar results were noted in older systematic reviews [75,76,86]. However, implementation of exercise training programs before esophageal cancer surgery has not resulted in similar beneficial effects [73,74,86].
•Cardiovascular surgery – A 2019 systematic review of nonrandomized studies before cardiac surgery (seven studies) or vascular surgery (two studies) noted that preoperative exercise programs improved objective physical functioning and subjective measurements of quality of life (QOL) compared with controls . A 2019 network meta-analyses noted that evidence of benefit was strongest for use of IMT in prehabilitation efforts .
Cognitive prehabilitation — Preexisting cognitive impairment is common in patients who are older or have certain other risk factors. Some prehabilitation programs have included cognitive exercises. Details regarding preoperative assessment and interventions to potentially improve postoperative cognitive function are discussed in a separate topic. (See "Perioperative neurocognitive disorders in adults: Risk factors and mitigation strategies", section on 'Preoperative risk assessment and management'.)
●Identification of anxiety or depression – Some prehabilitation programs have included psychological screening and interventions to reduce preoperative stress and anxiety before major surgical procedures [3,88,89]. In rare cases, counselling or specialist psychological or psychiatric care may be necessary for a patient with severe anxiety or depression [13,90]. Notably, preoperative education alleviates anxiety by setting expectations regarding the patient's own role in the recovery process [91-97]. (See "Anesthetic management for enhanced recovery after major noncardiac surgery (ERAS)", section on 'Preoperative considerations'.)
In noncardiac surgical patients, preoperative anxiety or depression has been associated with impairment of functional recovery as well as with postoperative pain [91,92,98-101]. One study in cardiac surgical patients noted increased mortality risk in patients with preoperative anxiety .
●Interventions to reduce preoperative stress – Some prehabilitation programs employ targeted behavioral interventions to reduce preoperative stress and anxiety including progressive muscle relaxation techniques, cognitive behavioral therapy (CBT), virtual reality experiences, guided imagery, deep breathing, and mindful meditation [3,7,13,93,103-110]. Improvements in traditional surgical outcomes such as incidence of complications or hospital LOS have not been found [77,93,101,103,111-113]. However, beneficial patient-reported effects have included QOL indicators, improved mood and sense of physical well-being, less fatigue and somatic symptoms, and more rapid recovery.
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Enhanced recovery after surgery".)
SUMMARY AND RECOMMENDATIONS
●Definition of prehabilitation – Prehabilitation refers to interventions that aim to enhance functional capacity and optimize recovery after surgery. These may include nutritional assessment and supplementation, physical exercise programs, efforts to improve cognitive function, smoking cessation, and stress reduction. Multimodal approaches are likely optimal for most patients. (See 'Definition and outcomes' above.)
●Outcomes and limitations – There is limited evidence that various unimodal or multimodal prehabilitation programs reduce complications and hospital length of stay (LOS) and only for selected patient groups. Substantial heterogeneity among studies has contributed to inconsistent results. (See 'Outcome data and limitations' above.)
●Target patient populations
•Selected procedures – Research on multimodal prehabilitation has focused on patients undergoing major gastrointestinal tract or cardiothoracic surgical procedures. (See 'Selected surgical procedures' above.)
•Nutritional supplementation – Malnutrition is common in patients undergoing major surgical procedures. Preoperative assessment of nutritional status (figure 1) and interventions to treat malnutrition are addressed in separate topics:
•Smoking cessation – Smokers should be strongly encouraged to cease smoking for four to eight weeks before surgery to minimize risk of postoperative pulmonary complications, as discussed separately:
•Physical exercise programs – We screen patients undergoing major surgery for poor functional capacity based on whether they exhibit frailty, or have decreased mobility, inactivity, or other risk factors such as recent chemo- or radiotherapy. Assessment tests include gait speed, time to complete five chair sit-to-stand repetitions, dominant handgrip strength, and quadriceps femoris thickness. Training programs have included aerobic, resistance, flexibility, balance, and strength exercises, as well as inspiratory muscle training. Results are inconsistent, although decreases in pulmonary morbidity and hospital LOS have been noted in some studies. (See 'Physical exercise programs' above.)
•Interventions to improve cognitive function – Some prehabilitation programs include preoperative cognitive exercises in their prehabilitation programs, as discussed separately. (See "Perioperative neurocognitive disorders in adults: Risk factors and mitigation strategies", section on 'Preoperative risk assessment and management'.)
•Stress reduction – Some prehabilitation programs employ targeted behavioral interventions to reduce preoperative stress and anxiety (eg, progressive muscle relaxation techniques, cognitive behavioral therapy [CBT], virtual reality experiences, guided imagery, deep breathing, mindful meditation). Improvements in some patient-reported quality of life indicators have been noted. (See 'Stress reduction' above.)