[Cognitive functions and cerebral oxygenation of older patients after general and regional anaesthesia]

Nerve blocks or no nerve blocks for pain control after elective hip replacement (arthroplasty) surgery in adults

BACKGROUND

It is estimated that over 300,000 total hip replacements are performed each year in the USA. For European countries, the number of hip replacement procedures per 100,000 people performed in 2007 varied from less than 50 to over 250. To facilitate postoperative rehabilitation, pain must be adequately treated. Peripheral nerve blocks and neuraxial blocks have been proposed to replace or supplement systemic analgesia.

OBJECTIVES

We aimed to compare the relative effects (benefits and harms) of the different nerve blocks that may be used to relieve pain after elective hip replacement in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 12, 2016), MEDLINE (Ovid SP) (1946 to December Week 49, 2016), Embase (Ovid SP) (1980 to December week 49, 2016), CINAHL (EBSCO host) (1982 to 6 December 2016), ISI Web of Science (1973 to 6 December 2016), Scopus (from inception to December 2016), trials registers, and relevant web sites.

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) performed in adults undergoing elective primary hip replacement and comparing peripheral nerve blocks to any other pain treatment modality. We applied no language or publication status restrictions.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors. We contacted study authors.

MAIN RESULTS

We included 51 RCTs with 2793 participants; of these 45 RCTs (2491 participants: peripheral nerve block = 1288; comparators = 1203) were included in meta-analyses. There are 11 ongoing studies and three awaiting classification.Compared to systemic analgesia alone, peripheral nerve blocks reduced: pain at rest on arrival in the postoperative care unit (SMD -1.12, 95% CI -1.67 to -0.56; 9 trials, 429 participants; equivalent to 3.2 on 0 to 10 scale; moderate-quality evidence); risk of acute confusional status: risk ratio (RR) 0.10 95% CI 0.02 to 0.54; 1 trial, 225 participants; number needed to treat for additional benefit (NNTB) 12, 95% CI 11 to 22; very low-quality evidence); pruritus (RR 0.16, 95% CI 0.04 to 0.70; 2 trials, 259 participants for continuous peripheral nerve blocks; NNTB 4 (95% CI 4 to 8); very low-quality evidence); hospital length of stay (SMD -0.75, 95% CI -1.02 to -0.48; very low-quality evidence; 2 trials, 249 participants; equivalent to 0.75 day). Participant satisfaction increased (SMD 0.67, 95% CI 0.45 to 0.89; low-quality evidence; 5 trials, 363 participants; equivalent to 2.4 on 0 to 10 scale). We did not find a difference for the number of participants walking on postoperative day one (very low-quality evidence). Two nerve block-related complications were reported: one local haematoma and one delayed persistent paresis.Compared to neuraxial blocks, peripheral nerve blocks reduced the risk of pruritus (RR 0.33, 95% CI 0.19 to 0.58; 6 trials, 299 participants; moderate-quality evidence; NNTB 6 (95% CI 5 to 9). We did not find a difference for pain at rest on arrival in the postoperative care unit (moderate-quality evidence); number of nerve block-related complications (low-quality evidence); acute confusional status (very low-quality evidence); hospital length of stay (low quality-evidence); time to first walk (low-quality evidence); or participant satisfaction (high-quality evidence).We found that peripheral nerve blocks provide better pain control compared to systemic analgesia with no major differences between peripheral nerve blocks and neuraxial blocks. We also found that peripheral nerve blocks may be associated with reduced risk of postoperative acute confusional state and a modest reduction in hospital length of stay that could be meaningful in terms of cost reduction considering the increasing numbers of procedures performed annually.

AUTHORS' CONCLUSIONS

Compared to systemic analgesia alone, there is moderate-quality evidence that peripheral nerve blocks reduce postoperative pain, low-quality evidence that patient satisfaction is increased and very low-quality evidence for reductions in acute confusional status, pruritus and hospital length of stay .We found moderate-quality evidence that peripheral nerve blocks reduce pruritus compared with neuraxial blocks.The 11 ongoing studies, once completed, and the three studies awaiting classification may alter the conclusions of the review once assessed.

Neuroaxial versus general anaesthesia in geriatric patients for hip fracture surgery: does it matter?

The influence of the mode of anaesthesia on outcome of geriatric patients with hip fractures is a controversial issue in the medical literature. In the light of an ageing society, a conclusive answer to this question is of growing importance. The purpose of this review was to assess the effect of neuroaxial and general anaesthesia on mortality and morbidity in geriatric patients sustaining a hip fracture. Following a current literature search within the Pubmed and Cochrane database (1967-2010), 34 randomised controlled trials, 14 observational studies and eight reviews/meta-analysis publications were included. Potentially outcome-influencing factors such as mortality, deep vein thrombosis, pulmonary embolism, postoperative confusion and other anaesthesia-related outcomes were evaluated. After analysing the current literature with 56 references, covering 18,715 patients with hip fracture, it can be concluded that spinal anaesthesia is associated with significantly reduced early mortality, fewer incidents of deep vein thrombosis, less acute postoperative confusion, a tendency to fewer myocardial infarctions, fewer cases of pneumonia, fatal pulmonary embolism and postoperative hypoxia. General anaesthesia has the advantages of having a lower incidence of hypotension and a tendency towards fewer cerebrovascular accidents compared to neuroaxial anaesthesia. Otherwise, general anaesthesia and respiratory diseases were significant predictors of morbidity in hip fracture patients. These data suggest that regional anaesthesia is the preferred technique, but the limited evidence available does not permit a definitive conclusion to be drawn for mortality or other outcomes. For hip fracture surgery, the choice of anaesthesia (general or neuroaxial) is made by the anaesthesiologist and is based on the patient's preference, comorbidities, potential general postoperative complications and the clinical experience of the anaesthesiologist. The overall therapeutic approach in hip fracture care should be determined jointly by the orthopaedic surgeon, the geriatrician and the anaesthesiologist (multidisciplinary approach).

The effect of peribulbar block with ropivacaine on bi-hemispheric cerebral oxygen saturation in aged patients

We evaluated the effects of peribulbar block for eye surgery on bi-hemispheric regional cerebral oxygenation (rSO2)) of aged patients. In 66 adult patients, peribulbar block was performed using ropivacaine 10 mg.ml(-1) with hyaluronidase 100 IU.ml(-1). Cerebral oxygenation was monitored using continuous non-invasive, near-infrared spectroscopy. The rSO2 data on the side where the eye block was performed were evaluated as eye block side values, whereas the data recorded on the other side were taken as control values. Mean rSO2 values on the side where regional block was performed were not significantly different from control values (p > 0.05). Nevertheless, in several patients, a slight desaturation in the cerebral hemisphere on the block side was detected. Therefore, in aged patients, peribulbar block with ropivacaine does not significantly modify bi-hemispheric rSO2, but rSO2 monitoring during peribulbar block should be a field of future research in aged patients with brain injury or disease.