Peripheral nerve blocks for above knee amputation in high-risk patients

Abstract

Background and Aims:Above knee amputation (AKA) is associated with considerable mortality and morbidity. There is paucity of data describing the use of peripheral nerve blocks (PNB) as the sole anesthetic technique in high-risk patients undergoing AKA. Our objectives were to evaluate the use of PNB as sole anesthetic technique in the above-mentioned population and its clinical outcomes.Material and Methods:This was a retrospective descriptive study conducted in a tertiary hospital. For this study, patients with American Society of Anesthesiologist [ASA] IV physical status underwent AKA using PNB between January 2010 and December 2016, were identified. The primary outcome measured was the success of the operation. The secondary outcomes were block details, intraoperative hemodynamics, usage of sedation and analgesia, patients’ comorbidities, mortality rates at 30 days and one year.Results:Out of fifty-seven patients, the median age (interquartile range) was 74 (57 – 81) years and 60% were males. The results show 91% successfully underwent surgery with PNB (95% CI 81% to 96%). 95% required intraoperative sedation and analgesia. 67% received combined femoral, obturator and sciatic nerve blocks, in which nine cases had an additional lateral femoral cutaneous nerve block. Interestingly, 33% only received combined femoral and sciatic nerve blocks, and they required higher sedation analgesia (p = 0.013). The 30-day and one-year mortality were 12.3% & 47.4%. Majority had stable hemodynamics during the surgery.Conclusion:This study shows that PNB is a viable option for reliable anesthesia for AKA in high-risk patients. Combined FOS nerve block would reduce the dose for sedation–analgesia during the operation.

Spinal Anesthesia Using Ultra-Low-Dose Isobaric Bupivacaine with Intrathecal Morphine-Fentanyl for Bilateral Low Extremity Procedures in a Geriatric Patient with Recent Myocardial Infarction and Percutaneous Coronary Intervention

“…Furthermore, complete analgesia/anesthesia are sometimes elusive under PNB despite targeting femoral, lateral femoral cutaneous, obturator (anterior and posterior divisions) and sciatic nerves separately with LA volumes and concentrations approaching the maximum safe threshold – some authors have admitted to exceeding the recommended doses without adverse toxic effects. 3 , 4 …”

“…Conventional spinal anesthesia has been considered as the gold standard approach for lower limb surgeries but many authors agree that they are best avoided in patients with poor cardiovascular reserve because significant hemodynamic disruption might ensue. 4 , 9 Our ultra-low-dose technique helped us to maintain the MAP and avoid spinal-induced hypotension which is associated with perioperative adverse cardiac events. 10 Using ultra-low-dose neuraxial technique limits the blocked spinal segments, the extent of the sympathetic blockade and minimizes the effect on the systemic vascular resistance.…”

“…Peripheral nerve block (PNB) and low-dose unilateral spinal anesthesia has been shown to offer satisfactory anesthesia as well as good hemodynamic stability, going by a few case reports and case series of patients who underwent AKA. [3][4][5][6][7] Our test case was scheduled for bilateral lower extremity procedures which precluded the use of hyperbaric bupivacaine for a unilateral spinal block or performing PNB because of the greater risk of local anesthetic systemic toxicity (LAST). Furthermore, complete analgesia/anesthesia are sometimes elusive under PNB despite targeting femoral, lateral femoral cutaneous, obturator (anterior and posterior divisions) and sciatic nerves separately with LA volumes and concentrations approaching the maximum safe threshold -some authors have admitted to exceeding the recommended doses without adverse toxic effects.…”

“…There are few reports of peripheral nerve blocks (PNBs) and low-dose unilateral spinal anesthesia (SA) for above-knee amputation (AKA) in high-risk patients but an ultra-low-dose isobaric bupivacaine with intrathecal injections of morphine-fentanyl has not been reported. [3][4][5] We hereby describe our anesthetic management of this case.…”

Peripheral nerve blocks for above-the-knee amputation in a patient with COVID-19 pneumonia

“…The prevalence of the use of this technique is currently unknown. In a retrospective study of 57 high-risk patients, Chandran et al (2018) reported a 91% success rate for patients undergoing above-the-knee amputation under peripheral nerve blocks and sedation [ 5 ]. Not surprisingly, higher levels of sedation were required if only the femoral and sciatic nerves were blocked, rather than also blocking the obturator and lateral femoral cutaneous nerves.…”