‘This review is published as a Cochrane Review in the Cochrane Database of Systematic Reviews 2004, Issue 4. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Review.’ Roberts, I., Alderson, P., Bunn, F., Chinnock, P., Ker, K., Schierhout, G. 'Colloids versus crystalloids for fluid resuscitation in critically ill patients' Cochrane Database of Systematic Reviews 2004 (4) CD000567. DOI:10.1002/14651858.CD000567.pub2

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Colloids versus crystalloids for fluid resuscitation in critically ill patients

The technology and clinical understanding of anatomical sonography has evolved greatly over the past decade. In the Department of Anaesthesia and Intensive Care Medicine at the Medical University of Vienna, ultrasonography has become a routine technique for regional anaesthetic nerve block. Recent studies have shown that direct visualization of the distribution of local anaesthetics with high-frequency probes can improve the quality and avoid the complications of upper/lower extremity nerve blocks and neuroaxial techniques. Ultrasound guidance enables the anaesthetist to secure an accurate needle position and to monitor the distribution of the local anaesthetic in real time. The advantages over conventional guidance techniques, such as nerve stimulation and loss-of-resistance procedures, are significant. This review introduces the reader to the theory and practice of ultrasound-guided anaesthetic techniques in adults and children. Considering their enormous potential, these techniques should have a role in the future training of anaesthetists.

Ultrasound guidance in regional anaesthesia

The practice of perioperative fluid therapy is variable, ranging from ‘high volume’ to ‘dry’ regimen. A review of the data on the effect of ‘high volume’ perioperative fluid therapy suggests that the resulting overhydration may have deleterious effects on cardiac and pulmonary function, and on recovery of gastrointestinal motility (postoperative ileus), tissue oxygenation, wound healing and coagulation. These observations call for randomized studies of the effects of ‘high’ vs ‘low’ volume replacement therapy on postoperative morbidity, in order to establish evidence-based guidelines for perioperative fluid management. Perioperative fluid replacement has been, and still is, the focus of much debate. This debate has primarily focused on the various types of fluid components available for replacement therapy, and not on the actual amount of fluid administered.

Pathophysiology and clinical implications of perioperative fluid excess

Background
The majority of people with hip fracture are treated surgically, requiring anaesthesia

Objectives
To compare different types of anaesthesia for surgical repair of hip fractures (proximal femoral fractures) in adults

Search methods
We searched the Cochrane Bone, Joint and Muscle Trauma Group specialised register (November 2003), MEDLINE (1996 to February week 2 2004), EMBASE (1988 to 2004 week 10) and reference lists of relevant articles

Selection criteria
Randomised and quasi-randomised trials comparing different methods of anaesthesia for hip fracture surgery in adults The primary focus of this review was the comparison of regional (spinal or epidural) anaesthesia versus general anaesthesia The use of nerve blocks preoperatively or in conjunction with general anaesthesia is evaluated in another review The primary outcome was mortality

Data collection and analysis
Two reviewers independently assessed trial quality and extracted data

Main results
Twenty two trials, involving 2567 predominantly female and elderly patients, comparing regional anaesthesia with general anaesthesia were included All trials had methodological flaws and many do not reflect current anaesthetic practice Pooled results from eight trials showed regional anaesthesia to be associated with a decreased mortality at one month (56/811 (69%) versus 86/857 (100%)); however, this was of borderline statistical significance (relative risk (RR) 069, 95% confidence interval (CI) 050 to 095) The results from six trials for three month mortality were not statistically significant, although the confidence interval does not exclude the possibility of a clinically relevant reduction (86/726 (118%) versus 98/765 (128%), RR 092, 95% CI 071 to 121) The reduced numbers of trial participants at one year, coming exclusively from two trials, preclude any useful conclusions for long-term mortality (80/354 (226%) versus 78/372 (210%), RR 107, 95% CI 082 to 141)

Regional anaesthesia was associated with a reduced risk of deep venous thrombosis (39/129 (30%) versus 61/130 (47%); RR 064, 95% CI 048 to 086) However, this finding is insecure due to possible selection bias in the subgroups in whom this outcome was measured Regional anaesthesia was also associated with a reduced risk of acute postoperative confusion (11/117 (94%) versus 23/120 (192%), RR 050, 95% CI 026 to 095)

There was insufficient evidence to draw any conclusions from a further four included trials, involving a total of 179 participants, which compared other methods of anaesthesia (a 'light' general with spinal anaesthesia; intravenous ketamine; nerve blocks)

Authors' conclusions
Overall, there was insufficient evidence available from trials comparing regional versus general anaesthesia to rule out clinically important differences Regional anaesthesia may reduce acute postoperative confusion but no conclusions can be drawn for mortality or other outcomes

Anaesthesia for hip fracture surgery in adults

Background. Despite the growing interest in the use of ultrasound (US) imaging to guide performance of regional anaesthetic procedures such as peripheral nerve blocks, controversy still exists as to whether US is superior to previously developed nerve localization techniques such as the use of a peripheral nerve stimulator (PNS). We sought to clarify this issue by performing a systematic review and meta-analysis of all randomized controlled trials that have compared these two methods of nerve localization. Methods. We searched Ovid MEDLINE w , the Cochrane Central Register of Controlled Trials w , and Google Scholar databases and also the reference lists of relevant publications for eligible studies. A total of 13 studies met our criteria and were included for analysis. Studies were rated for methodological quality by two reviewers. Data from these studies were

Ultrasound guidance compared with electrical neurostimulation for peripheral nerve block: a systematic review and meta-analysis of randomized controlled trials

The use of ultrasound reduces the onset time, improves the quality of sensory block, and minimizes the risks associated with the supraclavicular approach for brachial plexus and stellate ganglion blockade. The present study was designed to evaluate whether ultrasound also facilitates the approach for 3-in-1 blocks. Forty patients (ASA physical status II or III) undergoing hip surgery after trauma were randomly assigned to two groups. In the ultrasound (US) group, 20 mL bupivaCaine 0.5% was administered under US guidance, whereas in the control group, the same amount and concentration of local anesthetic was administered with the assistance of a nerve stimulator (NS). After US- or NS-based identification of the femoral nerve, the local anesthetic solution was administered, and the distribution of the local anesthetic solution was visualized and recorded on videotape in the US group. The quality and the onset of the sensory block was assessed by using the pinprick test in the central sensory region of each of the three nerves and compared with the same stimulation on the contralateral leg every 10 min for 60 min. The rating was performed using a scale from 100% (uncompromised sensibility) to 0% (no sensory sensation). Heart rate, noninvasive blood pressure, and oxygen saturation were measured at short intervals for 60 min. The onset of sensory blockade was significantly shorter in Group US compared with Group NS (US 16 ? 14 min, NS 27 -C 16 min, P < 0.05). The quality of the sensory block after injection of the local anesthetic was also significantly better in Group US compared with Group NS (US 15% -C 10% of initial value, NS 27% + 14% of initial value, P < 0.05). A good analgesic effect was achieved in 95% of the patients in the US group and in 85% of the patients in the NS group. In the US group, visualization of the cannula tip, the femoral nerve, the major vessels, and the local anesthetic spread was possible in 85% of patients. Incidental arterial puncture (n = 3) was observed only in the NS group. We conclude that an USguided approach for 3-in-1 block reduces the onset time, improves the quality of the sensory block and minimizes the risks associated with this regional anesthetic technique. Implications: The onset time and the quality of a regional anesthetic technique for the lower extremity is improved by ultrasonographic nerve identification compared with older techniques. (Anesth Analg 1997;85:854-7) he 3-in-1 block, including the femoral nerve, the obturator nerve, and the lateral cutaneous femoral nerve, is a widely used regional anesthetic technique for many operations and for pain management of the lower extremity. Indications for the 3-in-1 block include operations and wound care of the thigh, muscle biopsy of the thigh, obturator paralysis for transurethral resection of the prostate and urinary bladder, and, in combination with the sciatic nerve block, all operations for one lower limb. For analgesic therapy, the 3-in-1 block can be used for hip fractures, stump pain after amputation of lower limb, and mobilization therapy of the knee and hip joint.

Ultrasonographic Guidance Improves Sensory Block and Onset Time of Three-in-One Blocks

https://rapm.bmj.com/content/rapm/23/6/584.full.pdf

Ultrasonographic guidance reduces the amount of local anesthetic for 3-in-1 blocks

Summary


Ultrasonography may offer significant advantages in regional anaesthesia of the upper and lower limbs. It is not known if the same advantages demonstrated in adults also apply to children. We therefore performed a prospective, randomised study comparing ultrasound visualisation to conventional nerve stimulation for infraclavicular brachial plexus anasesthesia in children. Forty children scheduled for arm and forearm surgery underwent infraclavicular brachial plexus blocks with ropivacaine 0.5 ml.kg−1 guided by either nerve stimulation or ultrasound visualisation. Evaluated parameters included sensory block quality, sensory block distribution and motor block. All surgical procedures were performed under brachial plexus anaesthesia alone. Direct ultrasound visualisation was successful in all cases and was associated with significant improvements when compared with the use of nerve stimulation: lower visual analogue scores during puncture (p = 0.03), shorter mean (median) sensory onset times (9 (5–15) min vs. 15 (5–25) min, p < 0.001), longer sensory block durations (384 (280–480) min vs. 310 (210–420) min, p < 0.001), and better sensory and motor block scores 10 min afrter block insertion. Ultrasound visualisation offers faster sensory and motor responses and a longer duration of sensory blockade than nerve stimulation in children undergoing infraclavicular brachial plexus blocks. In addition, the pain associated with nerve stimulation due to muscle contractions at the time of insertion is eliminated.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2044.2004.03669.x

Ultrasound guidance for infraclavicular brachial plexus anaesthesia in children

The three-in-one technique of simultaneously blocking the femoral, the lateral femoral cutaneous (LFC), and the obturator nerves by a single injection of a local anesthetic was first described in 1973, and it was suggested that the underlying mechanism was one of cephalad spread resulting in a block

Magnetic resonance imaging of the distribution of local anesthetic during the three-in-one block

Background The infraclavicular vertical brachial plexus block, first described by Kilka and co-workers, offers a more proximal spread of anaesthesia for the upper extremity than the classic axillary approach. In this technique, the puncture site is defined as lying at the exact centre of an infraclavicular line (k) between the jugular fossa and the ventral process of the acromion. Our study was designed to determine whether the point so defined (P) corresponds with the optimal puncture site determined sonographically (S) and to develop an improved prediction model. Method High-resolution ultrasonography was carried out in 59 volunteers to visualize the plexus. Sonography-derived distances and morphometric measurements were used to test accuracy and calculate multiple regressions. Results We found a clear trend towards a more lateral puncture site. In women, S was significantly (P Conclusions The suggested modification should help to increase the success rate of the infraclavicular vertical brachial plexus block while decreasing the rate of potentially severe complications, although individual ultrasonographic guidance is to be recommended whenever possible.

P. Marhofer

Papers

Ultrasonographic Guidance Improves Sensory Block and Onset Time of Three-in-One Blocks

Ultrasonographic guidance reduces the amount of local anesthetic for 3-in-1 blocks

Ultrasound guidance for infraclavicular brachial plexus anaesthesia in children

Magnetic resonance imaging of the distribution of local anesthetic during the three-in-one block

Ultrasonographic assessment of topographic anatomy in volunteers suggests a modification of the infraclavicular vertical brachial plexus block