SummaryThe serratus anterior plane block has been described for analgesia of the hemithorax. This study was conducted to determine the spread of injectate and investigate the anatomical basis of the block. Ultrasound-guided serratus anterior plane block was performed on six soft-fix embalmed cadavers. All cadavers received bilateral injections, on one side performed with 20 ml latex and on the other with 20 ml methylene blue. Subsequent dissection explored the extent of spread and nerve involvement. Photographs were taken throughout dissection. The intercostal nerves were involved on three occasions with dye, but not with latex. The lateral cutaneous branches of the intercostal nerve contained dye and latex on all occasions. The serratus plane block appears to be mediated through blockade of the lateral cutaneous branches of the intercostal nerves. Anatomically, serratus plane block does not appear to be equivalent to paravertebral block for rib fracture analgesia.
There is no universally agreed set of anatomical structures that must be
identified on ultrasound for the performance of ultrasound-guided regional
anesthesia (UGRA) techniques. This study aimed to produce standardized
recommendations for core (minimum) structures to identify during seven basic
blocks. An international consensus was sought through a modified Delphi
process. A long-list of anatomical structures was refined through serial
review by key opinion leaders in UGRA. All rounds were conducted remotely
and anonymously to facilitate equal contribution of each participant. Blocks
were considered twice in each round: for “orientation scanning” (the dynamic
process of acquiring the final view) and for the “block view” (which
visualizes the block site and is maintained for needle insertion/injection).
Strong recommendations for inclusion were made if ≥75% of participants rated
a structure as “definitely include” in any round. Weak recommendations were
made if >50% of participants rated a structure as “definitely include” or
“probably include” for all rounds (but the criterion for “strong
recommendation” was never met). Thirty-six participants (94.7%) completed
all rounds. 128 structures were reviewed; a “strong recommendation” is made
for 35 structures on orientation scanning and 28 for the block view. A “weak
recommendation” is made for 36 and 20 structures, respectively. This study
provides recommendations on the core (minimum) set of anatomical structures
to identify during ultrasound scanning for seven basic blocks in UGRA. They
are intended to support consistent practice, empower non-experts using basic
UGRA techniques, and standardize teaching and research.
Percutaneous nephrostolithotomy in obese patients yields a stone-free rate that is comparable to that achieved in an unselected patient population. The complication rate, transfusion rate and hospital stay are also similar. Modifications to standard technique and instrumentation are sometimes necessary to perform percutaneous nephrostolithotomy in this group of patients.
SummaryRib fractures are associated with significant morbidity and mortality. Ultrasound‐guided thoracic paravertebral catheter insertion has been described for the management of pain secondary to rib fractures. We conducted a retrospective observational study of all patients with rib fractures who had a paravertebral catheter inserted for analgesia provision over a 4‐year period. Data from the Trauma Audit and Research Network were used to compare patients with rib fractures who were managed with paravertebral catheters to those managed with systemic analgesia. A total of 314 consecutive paravertebral catheters were inserted in 290 patients. Five (1.9%) catheters were removed due to ineffective analgesia. Other minor complications occurred in three cases (0.96%). The proportion of rib fracture patients managed with paravertebral catheters increased from 31/200 (15.5%) in the first year of study to 81/168 (48.2%) in the fourth; over this time‐period the observed:predicted mortality ratio fell from 1.04 to 0.66. Proportional hazard regression with and without propensity score matching demonstrated a reduction in mortality associated with paravertebral catheter use, but this became statistically non‐significant when time‐dependent analysis was used. Paravertebral catheters are a safe and effective technique for rib fracture analgesia; however, our data were insufficient to demonstrate any improvement in mortality.
Recent recommendations describe a set of core anatomical structures to identify on ultrasound for the performance of basic blocks in ultrasound-guided regional anesthesia (UGRA). This project aimed to generate consensus recommendations for core structures to identify during the performance of intermediate and advanced blocks. An initial longlist of structures was refined by an international panel of key opinion leaders in UGRA over a three-round Delphi process. All rounds were conducted virtually and anonymously. Blocks were considered twice in each round: for “orientation scanning” (the dynamic process of acquiring the final view) and for “block view” (which visualizes the block site and is maintained for needle insertion/injection). A “strong recommendation” was made if ≥75% of participants rated any structure as “definitely include” in any round. A “weak recommendation” was made if >50% of participants rated it as “definitely include” or “probably include” for all rounds, but the criterion for strong recommendation was never met. Structures which did not meet either criterion were excluded. Forty-one participants were invited and 40 accepted; 38 completed all three rounds. Participants considered the ultrasound scanning for 19 peripheral nerve blocks across all three rounds. Two hundred and seventy-four structures were reviewed for both orientation scanning and block view; a “strong recommendation” was made for 60 structures on orientation scanning and 44 on the block view. A “weak recommendation” was made for 107 and 62 structures, respectively. These recommendations are intended to help standardize teaching and research in UGRA and support widespread and consistent practice.
Yang et al. described an interesting cadaveric study showing the differences and similarities in anatomical spread of injectate for two types of paraspinal block: retrolaminar and erector spinae plane (ESP) [1]. Costache et al. describe these blocks as 'paravertebral by proxy' as neither require direct entry into the paravertebral space, yet still achieve blockade of the thoracic spinal nerves [2].There is some contention regarding the anatomical basis of the paravertebral spread in these blocks [1,[3][4][5].The reasons for these differences may stem from the fact that there is currently no standardised method to model the spread of local anaesthetic (LA) in cadaveric studies.There is abundant variation in mixtures of injectate that are used as a surrogate for LA in order to visualise spread upon dissection [1,3,4,6]. In addition, the mechanism for how LA travels through tissues is unknown even in living humans. Is spread reliant on conduction by mass effect along tissue planes, or is it by diffusion? The injectates used in these studies are likely to have different densities and biochemical properties in comparison with LA. This 126
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