Regional Anesthesia

Lung Resection, Anesthetic Technique and ICU Admission

This retrospective study examined Total Intravenous Anesthesia (TIVA), volatile inhalational anesthesia, and analgesic techniques of epidural or paravertebral block. Lung resection was the specific focus.

The aim was to investigate the influence of anaesthetic and analgesic technique on the need for unplanned postoperative intensive care admission – defined as the unplanned need for either tracheal intubation and mechanical ventilation or renal replacement therapy.

It was found that patients having TIVA or epidurals were less likely to have an unplanned admission to intensive care.

Mortality and length of stay was higher in those needing unplanned ICU admission.

The study discusses possible mechanisms for these findings but emphasizes that prospective randomized trials are needed to prove causation.


Rib Fracture Analgesia

Rib fractures cause significant impairment of respiratory function and are often accompanied by severe pain. Two studies add to our knowledge.

The first used ultrasound guided paravertebral block. While they couldn’t definitely prove any mortality benefit, they found it safe, effective and with low complication rate.

The second used potentially easier Erector Spinae plane blocks, which were associated with improved inspiratory capacity and analgesic outcomes following rib fracture, without haemodynamic instability. Opioid consumption was not reduced however.



Intermittent Lumbar Plexus Block vs. Continuous

A clear trend towards programmed intermittent bolus rather than continuous infusion has emerged in epidural analgesia in labor. Other regional analgesia pain blocks have found the same.

This study using lumber plexus block in total hip arthroplasty again finds intermittent rather than continuous infusion led to lower opioid rescue and more consistently maintained sensory block.

The regime was: continuous infusion group 6 mL/hour continuous infusion of levobupivacaine 0.125%, and intermittent infusion group 12 mL of levobupivacaine 0.125% bolus delivered every 2 hours.


Intravenous Dexmedetomidine and Dexamethasone for Postop Analgesia

Many agents have been added to peripheral nerve blocks to prolong analgesia. In some cases intravenous administration has been as successful without potential nerve toxicity concerns.

This small randomized study evaluated the difference in time to first rescue analgesic request between patients receiving co-administered intravenous dexamethasone and dexmedetomidine and patients receiving intravenous dexamethasone alone after single-shot interscslene brachial plexus block for arthroscopic shoulder surgery. Saline controls were used.

Co-administration of intravenous dexamethasone (0.11 mg kg−1) with dexmedetomidine (1.0 μg kg−1) significantly prolonged the time to first rescue analgesic request more than Dexamethasone alone, and both more so than saline controls. Also both groups had reduced postoperative opioid consumption, less sleep disruption and improved patient satisfaction compared with the control group.


Dexmedetomidine vs. Midazolam for Intraoperative Sedation

The reputation of benzodiazepines continues to take a hit.

This study compared older patients undergoing regional anesthesia and receiving intraoperative sedation. Dexmedetomidine wins, with Midazolam associated with higher psychomotor agitation, arterial hypotension, and respiratory depression.

During postanesthesia care, the incidence rates of shivering, residual sedation, and use of supplemental oxygen were significantly lower in the Dexmedetomidine group.


Perioperative Sleep Apnea & Regional Anesthesia

This study was retrospective with unaccounting for many variables such as concomitant sedation and does not prove causation, but found even in a setting with almost universal regional anesthesia for total knee and hip arthroplasties, OSA was associated with significantly increased odds for prolonged length of stay, pulmonary and gastrointestinal complications.

It nonetheless calls for further randomized studies in such a population, as neuraxial anesthesia is often felt to be a safer option.


Perioperative Epidurals and Delirium

A secondary observational non-randomized analysis of the PODCAST trial found that “postoperative epidural use was not associated with a reduced overall incidence of delirium. However, longitudinal analysis revealed reduced adjusted odds of experiencing an episode of delirium in the epidural group. Epidural use was also associated with reduced postoperative pain and opioid consumption”.

This study lends support to further randomized studies to study Epidural analgesia and delirium, even though previous work does not strongly support any particular form of anesthesia for delirium prevention.


General Anesthesia for Cesarean

This retrospective study spanned a decade but included nearly half a million Cesarean Sections in New York State.

5.7% were classified as GA without a recorded indication. The study found: “The use of potentially avoidable general anesthesia in these patients is associated with an increased risk of anesthesia-related complications, surgical site infection, and venous thromboembolism, but not death or cardiac arrest”. The odds were quite significantly higher.

Risk factors for GA included age less than 19, racial or ethnic minority, Medicaid or Medicare beneficiaries, preexisting or pregnancy-associated conditions, nonelective admission, and admission during weekend, teaching hospital, neonatal level-of-care designation 1 or 3, lower use of neuraxial techniques during labor and vaginal deliveries, higher annual volume of deliveries, and higher proportion of women with a comorbidity index greater than 2.

Neuraxial anesthesia is established as the standard of care in Cesarean anesthesia absent contraindication. Higher labor epidural rates appeared to be the most actionable factor to encourage and increase the odds of neuraxial anesthesia.

Many of the other factors are either known or subject to the limitations of this retrospective study, and may be subject to coding inaccuracy, malfunctioning epidural catheters, or patient request.