Postoperative orthostatic intolerance following fast-track unicompartmental knee arthroplasty: incidence and hemodynamics-a prospective observational cohort study

BACKGROUND

Early postoperative mobilization is essential for early functional recovery but can be inhibited by postoperative orthostatic intolerance (OI). Postoperative OI is common after major surgery, such as total knee arthroplasty (TKA). However, limited data are available after less extensive surgery, such as unicompartmental knee arthroplasty (UKA). We, therefore, investigated the incidence of OI as well as cardiovascular and tissue oxygenation responses during early mobilization after UKA.

METHODS

This prospective single-centre observational study included 32 patients undergoing primary UKA. Incidence of OI and cardiovascular and tissue oxygenation responses during mobilization were evaluated preoperatively, at 6 and 24 h after surgery. Perioperative fluid balance, bleeding, surgery duration, postoperative hemoglobin, pain during mobilization and opioid usage were recorded.

RESULTS

During mobilization at 6 h after surgery, 4 (14%, 95%CI 4-33%) patients experienced OI; however, no patients terminated the mobilization procedure prematurely. Dizziness and feeling of heat were the most common symptoms. OI was associated with attenuated systolic and mean arterial blood pressure responses in the sitting position (all p < 0.05). At 24 h after surgery, 24 (75%) patients had already been discharged, including three of the four patients with early OI. Only five patients were available for measurements, two of whom experienced OI; one terminated the mobilization procedure due to intolerable symptoms. We observed no statistically significant differences in perioperative fluid balance, bleeding, surgery duration, postoperative hemoglobin, pain, or opioid usage between orthostatic intolerant and tolerant patients.

CONCLUSIONS

The incidence of orthostatic intolerance after fast-track unicompartmental knee arthroplasty is low (~ 15%) and is associated with decreased orthostatic pressure responses. Compared to the previously described orthostatic intolerance incidence of ~ 40% following total knee arthroplasty, early orthostatic intolerance is uncommon after unicompartmental knee arthroplasty, suggesting a procedure-specific component.

TRIAL REGISTRATION

Prospectively registered at ClinicalTrials.gov; registration number: NCT04195360, registration date: 13.12.2019.

Patent landscape review of non-invasive medical sensors for continuous monitoring of blood pressure and their validation in critical care practice

Objectives

Continuous non-invasive monitoring of blood pressure is one of the main factors in ensuring the safety of the patient's condition in anesthesiology, intensive care, surgery, and other areas of medicine. The purpose of this work was to analyze the current patent situation and identify directions and trends in the application of non-invasive medical sensors for continuous blood pressure monitoring, with a focus on clinical experience in critical care and validation thereof.

Materials and methods

The research results reflect data collected up to September 30, 2022. Patent databases, Google Scholar, the Lens database, Pubmed, Scopus databases were used to search for patent and clinical information.

Results

An analysis of the patent landscape indicates a significant increase in interest in the development of non-invasive devices for continuous blood pressure monitoring and their implementation in medical practice, especially in the last 10 years. The key players in the intellectual property market are the following companies: Cnsystems Medizintechnik; Sotera Wireless INC; Tensys Medical INC; Healthstats Int Pte LTD; Edwards Lifesciences Corp, among others. Systematization of data from validation and clinical studies in critical care practice on patients with various pathological conditions and ages, including children and newborns, revealed that a number of non-invasive medical sensor technologies are quite accurate and comparable to the "gold standard" continuous invasive blood pressure monitoring. They are approved by the FDA for medical applications and certified according to ISO 81060-2, ISO 81060-3, and ISO/TS 81060-5. Unregistered and uncertified medical sensors require further clinical trials.

Conclusion

Non-invasive medical sensors for continuous blood pressure monitoring do not replace, but complement, existing methods of regular blood pressure measurement, and it is expected to see more of these technologies broadly implemented in the practice in the near future.

Prevalence and associated factors of postoperative orthostatic intolerance at University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia, 2022: cross sectional study

BACKGROUND

Postoperative orthostatic intolerance is an inability to maintain an upright position because of symptoms of cerebral hypoperfusion. It is a common problem in the early postoperative period and hinders early mobilization, however, there is limited information about factors associated with it. Thus, the main aim of this study was to determine the prevalence and identify factors associated with postoperative orthostatic intolerance.

METHOD

Hospital based cross-sectional study was conducted from April 08 to July 20, 2022, at University of Gondar comprehensive Specialized Hospital. A semi-structured questionnaire containing sociodemographic variables and perioperative factors related to anesthesia and surgery was used for data collection. The presence of postoperative orthostatic intolerance during the first ambulation was evaluated with a standardized symptom checklist which contains symptoms of orthostatic intolerance. Binary logistic regression analysis was performed to assess factors associated with postoperative orthostatic intolerance. In multivariable regression, variables with P-value < 0.05 were considered statistically significant.

RESULT

A total of 420 patients were included in this study with a response rate of 99.06%. Postoperative orthostatic intolerance was experienced in 254 (60.5%) participants. Being female (AOR = 2.27; 95% CI = 1.06-4.86), low BMI (AOR = 0.79; 95% CI = 0.71-0.95), ASA II and above (AOR = 3.34; 95% CI = 1.34-8.28), low diastolic blood pressure (AOR = 0.82; 95% CI = 0.88-0.99), general anesthesia (AOR = 3.26, 95% CI = 1.31-8.12), high intraoperative blood lose (AOR = 0.93, 95% CI = 0.88-0.99), high postoperative fluid intake (AOR = 2.09, 95% CI = 1.23-3.55), pain before ambulation (AOR = 1.99, 95% CI = 1.28-3.11) and pain during ambulation (AOR = 1.82, 95% CI = 1.23-2.69) were the significant factors associated with orthostatic intolerance.

CONCLUSION

Our study revealed that postoperative orthostatic intolerance was experienced in nearly two-thirds of participants. During the time of ambulation, assessing patients for the presence of orthostatic intolerance is necessary to reduce the adverse effects of postoperative OI. In addition, maintaining preoperative normotension, reducing intraoperative blood loss and optimizing postoperative pain control is recommended to reduce the risk of postoperative orthostatic intolerance.

Orthostatic intolerance after fast-track knee arthroplasty: Incidence and hemodynamic pathophysiology

BACKGROUND

Early postoperative mobilization can be hindered by orthostatic intolerance (OI) due to failed orthostatic cardiovascular regulation. The underlying mechanisms are not fully understood and specific data after total knee arthroplasty (TKA) are lacking. Therefore, we evaluated the incidence of OI and the cardiovascular response to mobilization in fast-track TKA.

METHODS

This prospective observational cohort study included 45 patients scheduled for primary TKA in spinal anesthesia with a multimodal opioid-sparing analgesic regime. OI and the cardiovascular response to sitting and standing were evaluated with a standardized mobilization procedure preoperatively, and at 6h and 24h postoperatively. Hemodynamic variables were measured non-invasively (LiDCO™ Rapid). Perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, opioid use and pain during mobilization were recorded.

RESULTS

Eighteen (44%) and 8 (22%) patients demonstrated OI at 6 and 24h after surgery respectively. Four (10%) and 2 (5%) patients experienced severe OI and terminated the mobilization procedure prematurely. Dizziness was the most common OI symptom during mobilization at 6h. OI was associated with decreased orthostatic responses in systolic, diastolic, mean arterial pressures and heart rate (all p<0.05), while severe OI patients demonstrated impaired diastolic, mean arterial pressures, heart rate and cardiac output responses (all p<0.05). No statistically significant differences in perioperative bleeding, fluid balance, surgery duration, postoperative hemoglobin, pain or opioid use were observed between orthostatic tolerant and intolerant patients.

CONCLUSION

Early postoperative OI is common following fast-track TKA. Pathophysiologic mechanisms include impaired orthostatic cardiovascular responses. The progression to severe OI symptoms appears to be primarily due to inadequate heart rate response.

Shedding light on pain for the clinic: a comprehensive review of using functional near-infrared spectroscopy to monitor its process in the brain

ABSTRACT

Pain is a complex experience that involves sensation, emotion, and cognition. The subjectivity of the traditional pain measurement tools has expedited the interest in developing neuroimaging techniques to monitor pain objectively. Among noninvasive neuroimaging techniques, functional near-infrared spectroscopy (fNIRS) has balanced spatial and temporal resolution; yet, it is portable, quiet, and cost-effective. These features enable fNIRS to image the cortical mechanisms of pain in a clinical environment. In this article, we evaluated pain neuroimaging studies that used the fNIRS technique in the past decade. Starting from the experimental design, we reviewed the regions of interest, probe localization, data processing, and primary findings of these existing fNIRS studies. We also discussed the fNIRS imaging's potential as a brain surveillance technique for pain, in combination with artificial intelligence and extended reality techniques. We concluded that fNIRS is a brain imaging technique with great potential for objective pain assessment in the clinical environment.

Effect of using elastic-pressure socks in spinal surgery patients on orthostatic hypotension in the first mobilization

BACKGROUND

Orthostatic hypotension (OH) is a common early postoperative finding in patients who undergo major surgery, and it might delay early mobilization, which is the main building block of modern perioperative care programs. The aim of this study was to determine the effect of using thigh-length elastic pressure socks in patients who undergo spinal surgery in development of OH at first mobilization after surgery.

METHODS

The study was a randomized-controlled intervention study. A total of 70 patients who underwent spinal surgery were included in the study. The patients were allocated randomly to the intervention group (n = 35) who used thigh-length elastic pressure socks and the control group (n = 35) which received no intervention other than routine nursing care.

RESULTS

It was found in the study that 2.9% of the patients in the intervention group developed OH during the first mobilization after the surgery, and 48.6% of the patients in the control group developed OH at first mobilization. The patients in the intervention group were found to have the risk ratio (RR): 0.06 times less probability of developing OH than the patients in the control group (95% confidence interval [CI]:0.01-0.42). The OH symptoms were lower in the patients in the intervention group.

CONCLUSION

It was found as a result of the study that using thigh-length elastic pressure socks in spinal surgery patients reduced OH development and symptoms at first mobilization after the surgery.

What Is the Evidence for Early Mobilisation in Elective Spine Surgery? A Narrative Review

Early mobilisation is a cornerstone of Enhanced Recovery after Surgery (ERAS) and is encouraged following spinal procedures. However, evidence of its implementation is limited and there are no formal guidelines on optimal prescription. This narrative review aimed to evaluate the evidence for the effect of early mobilisation following elective spinal surgery on length of stay, postoperative complications, performance-based function and patient-reported outcomes. Four trials (five articles) that compared a specific protocol of early in-hospital mobilisation to no structured mobilisation or bed rest were selected for inclusion. Nine studies that investigated the implementation of a multimodal intervention that was inclusive of an early mobilisation protocol were also included. Results suggest that goal-directed early mobilisation, delivered using an evidence-based algorithm with a clear, procedure-specific inclusion and exclusion criteria, may reduce length of stay and complication rate. In addition, there is evidence to suggest improved performance-based and patient-reported outcomes when compared to bed rest following elective spinal surgery. Whilst this review reveals a lack of evidence to determine the exact details of which early mobilisation protocols are most effective, mobilisation on the day of surgery and ambulation from the first postoperative day is possible and should be the goal. Future work should aim to establish consensus-based, best practice guidelines on the optimal type and timing of mobilisation, and how this should be modified for different spinal procedures.

Orthostatic intolerance in enhanced recovery laparoscopic colorectal resection

BACKGROUND

Orthostatic hypotension (OH) and intolerance (OI) are common findings in the early postoperative period after major surgery and may delay early mobilization. The mechanism of impaired orthostatic competence and OI symptoms is not fully understood, and specific data after colorectal surgery with well-defined perioperative care regimens and mobilization protocols are lacking. The aim of this study was to investigate the prevalence, possible risk factors and the impact of OI in patients undergoing elective minimal invasive colorectal cancer resection.

METHODS

A prospective single-centre study with an optimal enhanced recovery program and multimodal analgesic treatment. OI and OH were evaluated using a well-defined mobilization protocol preoperatively and 6 hour and 24 hour postoperatively.

RESULTS

A total of 100 patients were included in the data analysis. The overall median length of stay was 3 days (1-38). OI was observed in 53% of the patients 6 hour postoperatively and in 24% at 24 hour. OI at 6 hour postoperatively was associated with younger age, lower BMI, and female gender. At 24 hour postoperatively, female gender and ASA class >1 was associated with OI. Opioid consumption and intravenous fluid during the first 24 hour was not associated with OI. Postoperative complications were equally observed between patients with and without OI. Although not statistically significant, patients with OI at 24 hour postoperatively had prolonged LOS (mean 4.0 vs 7.5 days, P = 0.069) compared with patients without OI.

CONCLUSION

Postoperative orthostatic intolerance is a common problem during the first 24 hour following laparoscopic colorectal resection and may be followed by delayed recovery.

Changes in the augmentation index and postoperative orthostatic intolerance in orthopedic surgery: a prospective cohort study

BACKGROUND

Postoperative orthostatic intolerance (OI) can be a major obstacle to early ambulation and its determinants are poorly understood. We aimed to study postoperative changes in vascular tone and their potential association with OI in various orthopedic surgical settings.

METHODS

In this prospective cohort study, 350 patients undergoing total joint arthroplasty under neuraxial anesthesia or spine surgery under general anesthesia were enrolled. We determined the augmentation index (AI) as a measure of vascular tone and studied symptoms of OI using a validated questionnaire at various postoperative time points.

RESULTS

The AI was significantly reduced postoperatively (at spinal resolution in patients with neuraxial anesthesia or two hours postoperatively in general anesthesia) compared with baseline values in all procedures and did not subsequently return to baseline throughout the postoperative period in the majority of patients [252/335 (75.2%); P < 0.001]. The majority [260/342 (76.0%); P < 0.001] of patients had postoperative symptoms of OI. Nevertheless, no association was found between postoperative change in AI from baseline and postoperative symptoms of OI.

CONCLUSIONS

A significantly prolonged decrease in AI and symptoms of OI are common after orthopedic surgery. Nevertheless, an association between the two measures was not observed. While compensatory mechanisms may limit the influence of an AI decrease on symptoms of OI, more research is needed to understand the contributing factors and aid in the identification of patients at risk of OI.

Experience of Immediate Ambulation and Early Discharge After Tumescent Anesthesia and Propofol Infusion in Cosmetic Breast Augmentation

INTRODUCTION

Current cosmetic breast augmentation relies on general anesthesia that normally requires 40 min to total recovery. With experience, the surgical procedure can be completed expediently in 20 min under tumescent anesthesia and propofol full sedation to achieve immediate postoperative ambulation and home discharge readiness, and thus improve patient satisfaction and reduce cost. We retrospectively examined the outcomes of the protocol.

MATERIALS AND METHODS

Per protocol, 1200 female patients underwent simple cosmetic breast augmentation accomplished with tumescent anesthesia, immediate mobilization, and early home discharge readiness after surgery. The following records were analyzed: vital sign stability during mobilization in the first 30 cases (primary goal), duration of surgery and anesthesia, frequency of intraoperative opioid use, frequency of ambulation needing assistance, Verbal Analog Scores and incidences of pain, orthostatic intolerance events, incidences of postoperative nausea and vomiting or anti-emetic use, and complications at follow-up visits (secondary goal).

RESULTS

Hemodynamics during immediate postoperative mobilization demonstrated no statistically significant fluctuations and/or orthostatic intolerance requiring interventions. The mean duration of surgery was 20.4 ± 4.1 min. The mean duration of anesthesia was 25.2 ± 6.8 min. All patients tolerated immediate postoperative ambulation well. Adverse postoperative events were scarce. Only 9.1% reported postoperative pain, and 5.7% reported postoperative nausea and vomiting. One percent had transit post-ambulation dizziness needing supine positioning for less than 3 min. The average time to meet home-readiness criteria was 4.7 min, and there was no incidence of hematoma, infection, or complaints at follow-ups.

CONCLUSIONS

For simple cosmetic breast augmentation, instead of general anesthesia and 40 min of recovery time, a tumescent anesthetic technique can be used for immediate postoperative ambulation and a 4.7-min home discharge readiness without a decrease in anesthesia quality and safety.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Incidence of orthostatic hypotension and cardiovascular response to postoperative early mobilization in patients undergoing cardiothoracic and abdominal surgery

BACKGROUND

In cardiothoracic and abdominal surgery, postoperative complications remain major clinical problems. Early mobilization has been widely practiced and is an important component in preventing complications, including orthostatic hypotension (OH) during postoperative management. We investigated cardiovascular response during early mobilization and the incidence of OH after cardiothoracic and abdominal surgery.

METHODS

In this prospective observational study, we consecutively analyzed data from 495 patients who underwent elective cardiothoracic and abdominal surgery. We examined the incidence of OH, and the independent risk factors associated with OH during early mobilization after major surgery. Multivariate logistic regression was performed using various characteristics of patients to identify OH-related independent factors.

RESULTS

OH was observed in 191 (39%) of 495 patients. The incidence of OH in cardiac, thoracic, and abdominal groups was 39 (33%) of 119, 95 (46%) of 208, and 57 (34%) of 168 patients, respectively. Male sex (OR 1.538; p = 0.03) and epidural anesthesia (OR 2.906; p < 0.001) were independently associated with OH on multivariate analysis.

CONCLUSIONS

These results demonstrate that approximately 40% patients experience OH during early mobilization after cardiothoracic and abdominal surgery. Sex was identified as an independent factor for OH during early mobilization after all three types of surgeries, while epidural anesthesia was only identified after thoracic surgery. Therefore, the frequent occurrence of OH during postoperative early mobilization should be recognized.

TRIAL REGISTRATION

University hospital Medical Information Network Center (UMIN-CTR) number UMIN000018632 . (Registered on 1st October, 2008).

Early mobilization reduces the atelectasis and pleural effusion in patients undergoing coronary artery bypass graft surgery: A randomized clinical trial

Atelectasis and pleural effusion are common after coronary artery bypass graft surgery (CABG). Longer stay in the bed is one of the most important contributing factors in pulmonary complications. Some studies confirm the benefits of early mobilization (EM) in critically ill patients, but the efficacy of EM on pulmonary complications after CABG is not clear. This study was designed to examine the effect of EM on the incidence of atelectasis and pleural effusion in patients undergoing CABG. In a single-blinded randomized clinical trial, 100 patients who were undergoing coronary artery bypass graft surgery were randomly assigned into two groups each consisted of 50 patients. Patients in the experimental group were enrolled in a mobilization protocol consisting of the mobilization from the bed in the first 3 days after surgery in the morning and evening. Patients in the control group were mobilized from bed in third postoperation day, according to the hospital routine. Arterial blood gases, pleural effusion, and atelectasis were compared between groups. Atelectasis and pleural effusion was reduced in experimental group. The partial pressure of oxygen in arterial blood in third postoperative day and the percentage of arterial oxygen saturation in the fourth postoperative day were higher in the intervention group (P value < .05). EM from bed could be an effective intervention in reducing atelectasis and pleural effusion in patients undergoing CABG.

Hemodynamic challenge to early mobilization after cardiac surgery: A pilot study

Background:

Active mobilization is a key component in fast-track surgical strategies. Following major surgery, clinicians are often reluctant to mobilize patients arguing that circulatory homeostasis would be impaired as a result of myocardial stunning, fluid shift, and autonomic dysfunction.

Aims:

We examined the feasibility and safety of a mobilization protocol 12–24 h after elective cardiac surgery.

Setting and Design:

This observational study was performed in a tertiary nonacademic cardiovascular Intensive Care Unit.

Materials and Methods:

Over a 6-month period, we prospectively evaluated the hemodynamic response to a two-staged mobilization procedure in 53 consecutive patients. Before, during, and after the mobilization, hemodynamics parameters were recorded, including the central venous oxygen saturation (ScvO₂), lactate concentrations, mean arterial pressure (MAP), heart rate (HR), right atrial pressure (RAP), and arterial oxygen saturation (SpO₂). Any adverse events were documented.

Results:

All patients successfully completed the mobilization procedure. Compared with the supine position, mobilization induced significant increases in arterial lactate (34.6% [31.6%, 47.6%], P = 0.0022) along with reduction in RAP (−33% [−21%, −45%], P < 0.0001) and ScvO₂ (−7.4% [−5.9%, −9.9%], P = 0.0002), whereas HR and SpO₂ were unchanged. Eighteen patients (34%) presented a decrease in MAP > 10% and nine of them (17%) required treatment. Hypotensive patients experienced a greater decrease in ScvO₂ (−18 ± 5% vs. −9 ± 4%, P = 0.004) with similar changes in RAP and HR. All hemodynamic parameters, but arterial lactate, recovered baseline values after resuming the horizontal position.

Conclusions:

Early mobilization after cardiac surgery appears to be a safe procedure as far as it is performed under close hemodynamic and clinical monitoring in an intensive care setting.

Oral Midodrine Hydrochloride for Prevention of Orthostatic Hypotension during Early Mobilization after Hip Arthroplasty

Background

Early postoperative mobilization is essential for rapid recovery but may be impaired by orthostatic intolerance (OI) and orthostatic hypotension (OH), which are highly prevalent after major surgery. Pathogenic mechanisms include an insufficient postoperative vasopressor response. The oral α-1 agonist midodrine hydrochloride increases vascular resistance, and the authors hypothesized that midodrine would reduce the prevalence of OH during mobilization 6 h after total hip arthroplasty relative to placebo.

Methods

This double-blind, randomized trial allocated 120 patients 18 yr or older and scheduled for total hip arthroplasty under spinal anesthesia to either 5 mg midodrine hydrochloride or placebo orally 1 h before mobilization at 6 and 24 h postoperatively. The primary outcome was the prevalence of OH (decrease in systolic or diastolic arterial pressures of &gt; 20 or 10 mmHg, respectively) during mobilization 6 h after surgery. Secondary outcomes were OI and hemodynamic responses to mobilization at 6 and 24 h.

Results

At 6 h, 14 (25%; 95% CI, 14 to 38%) versus 23 (39.7%; 95% CI, 27 to 53%) patients had OH in the midodrine and placebo group, respectively, relative risk 0.63 (0.36 to 1.10; P = 0.095), whereas OI was present in 15 (25.0%; 15 to 38%) versus 22 (37.3%; 25 to 51%) patients, relative risk 0.68 (0.39 to 1.18; P = 0.165). At 24 h, OI and OH prevalence did not differ between groups.

Conclusions

Preemptive use of oral 5 mg midodrine did not significantly reduce the prevalence of OH during early postoperative mobilization compared with placebo. However, further studies on dose and timing are warranted since midodrine is effective in chronic OH conditions.

Decreased heart rate variability responses during early postoperative mobilization--an observational study

BACKGROUND

Intact orthostatic blood pressure regulation is essential for early mobilization after surgery. However, postoperative orthostatic hypotension and intolerance (OI) may delay early ambulation. The mechanisms of postoperative OI include impaired vasopressor responses relating to postoperative autonomic dysfunction. Thus, based on a previous study on haemodynamic responses during mobilization before and after elective total hip arthroplasty (THA), we performed secondary analyses of heart rate variability (HRV) and aimed to identify possible abnormal postoperative autonomic responses in relation to postural change.

METHODS

A standardized mobilization protocol before, 6 and 24 h after surgery was performed in 23 patients scheduled for elective THA. Beat-to-beat arterial blood pressure was measured by photoplethysmography and HRV was derived from pulse wave interbeat intervals and analysed in the time and frequency domain as well as by non-linear analysis using sample entropy

RESULTS

Before surgery, arterial pressures and HR increased upon standing, while HRV low (LF) and high frequency (HF) components remained unchanged. At 6 and 24 h after surgery, resting total HRV power, sample entropy and postural responses in arterial pressures decreased compared to preoperative conditions. During standing HF variation increased by 16.7 (95 % CI 8.0-25.0) normalized units (nu) at 6 h and 10.7 (2.0-19.4) nu at 24 h compared to the preoperative evaluation. At 24 h the LF/HF ratio decreased from 1.8 (1.2-2.6) nu when supine to 1.2 (0.8-1.8) nu when standing.

CONCLUSIONS

This study observed postoperative autonomic cardiovascular dysregulation that may contribute to limited HRV responses during early postoperative mobilization.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01089946.

Does Goal-directed Fluid Therapy Affect Postoperative Orthostatic Intolerance?

Background:

Early mobilization is important for postoperative recovery but is limited by orthostatic intolerance (OI) with a prevalence of 50% 6 h after major surgery. The pathophysiology of postoperative OI is assumed to include hypovolemia besides dysregulation of vasomotor tone. Stroke volume–guided fluid therapy, so-called goal-directed therapy (GDT), corrects functional hypovolemia, and the authors hypothesized that GDT reduces the prevalence of OI after major surgery and assessed this in a prospective, double-blinded trial.

Methods:

Forty-two patients scheduled for open radical prostatectomy were randomized into standard fluid therapy (control group) or GDT groups. Both groups received a fixed-volume crystalloid regimen supplemented with 1:1 replacement of blood loss with colloid, and in addition, the GDT group received colloid to obtain a maximal stroke volume (esophageal Doppler). The primary outcome was the prevalence of OI assessed with a standardized mobilization protocol before and 6 h after surgery. Hemodynamic and hormonal orthostatic responses were evaluated.

Results:

Twelve (57%) versus 15 (71%) patients in the control and GDT groups (P = 0.33), respectively, demonstrated OI after surgery, group difference 14% (CI, −18 to 45%). Patients in the GDT group received more colloid during surgery (1,758 vs. 1,057 ml; P = 0.001) and reached a higher stroke volume (102 vs. 89 ml; P = 0.04). OI patients had an increased length of hospital stay (3 vs. 2 days; P = 0.02) and impaired hemodynamic and norepinephrine responses on mobilization.

Conclusion:

GDT did not reduce the prevalence of OI, and patients with OI demonstrated impaired cardiovascular and hormonal responses to mobilization.

Evidence-based review of enhancing postoperative recovery after breast surgery

BACKGROUND

The introduction of enhanced recovery after surgery (ERAS) protocols has revolutionized preoperative and postoperative care. To date, however, the principles of enhanced recovery have not been applied specifically to patients undergoing breast surgery.

METHODS

Based on the core features of ERAS, individual aspects of postoperative care in breast surgery were defined. A comprehensive search of MEDLINE, PubMed, Embase and the Cochrane Library database was performed from 1980 to 2010 to determine the best evidence for perioperative care in oncological breast surgery. A graded recommendation based on the best level of evidence was then proposed for each feature of ERAS.

RESULTS

Twelve core features of enhanced recovery after breast surgery were identified. Use of the thoracic block, from both analgesic and anaesthetic viewpoints, is well supported by evidence and should be encouraged. Trials specific to breast surgery regarding aspects such as perioperative fasting, preanaesthetic medication, prevention of hypothermia and postdischarge support are scarce, and evidence was extrapolated from non-breast trials. Trials on postoperative analgesia and prevention of postoperative nausea and vomiting in breast surgery are generally of small numbers. In addition, there is heterogeneity between studies.

CONCLUSION

This review suggests that the principles of enhanced recovery can be adopted in breast surgery. A 12-point protocol is proposed for prospective evaluation.