No abstract

Preoperative BTA injection to the muscles of the anterolateral abdominal wall is a safe and effective technique for the preoperative preparation of patients prior to laparoscopic mesh repair of complex ventral hernia. This technique elongates and thins the contracted and retracted musculature, enabling closure of large defects.

BACKGROUND Spinal cord stimulation (SCS) activates the dorsal column fibers using electrical stimuli. Current SCS systems function in fixed-output mode, delivering the same stimulus regardless of spinal cord (SC) activation. OBJECTIVE To present long-term outcomes of a novel closed-loop SCS system that aims to maintain the SC activation near a set target level and within a therapeutic window for each patient. SC activation is measured through the evoked compound action potential (ECAP) generated by each stimulus pulse. METHODS Fifty patients with lower back and/or leg pain who were successfully trialed received a permanent system (Evoke; Saluda Medical, Sydney, Australia). Ratings of pain (visual analog scale), quality of life, function, sleep, and medication use were collected at baseline and at each visit. SC activation levels were reported in summary statistics. The therapeutic window for each individual patient was defined as the range of ECAP amplitudes between sensation threshold and uncomfortably strong stimulation. RESULTS At 12 mo, the proportion of patients with ≥50% relief was 76.9% (back), 79.3% (leg), and 81.4% (overall), and the proportion with ≥80% pain relief was 56.4% (back), 58.6% (leg), and 53.5% (overall). Patients spent a median of 84.9% of their time with stimulation in their therapeutic window, and 68.8% (22/32) eliminated or reduced their opioid intake. Statistically significant improvements in secondary outcomes were observed. CONCLUSION The majority of patients experienced more than 80% pain relief with stable SC activation, as measured by ECAP amplitude at 12 mo, providing evidence for the long-term effectiveness of the Evoke closed-loop SCS system.

Introduction: Chronic pain is a major public health concern, as is the associated use of opioid medications, highlighting the importance of alternative treatments, such as spinal cord stimulation (SCS). Here, we present the final 24-month results of the Avalon study, which investigated the use of the first closed-loop SCS system in patients with chronic pain. The system measures the evoked compound action potentials (ECAPs) elicited by each stimulus pulse and drives a feedback loop to maintain the ECAP amplitude near constant. Methods: Fifty patients were implanted with the Evoke system (Saluda Medical) and followed over 24-months. Pain, quality of life (QOL), function, sleep, and medication use were collected at baseline and each scheduled visit. ECAP amplitudes and programming adjustments were also monitored. Results: At 24 months, responder rates (≥ 50% pain reduction) and high responder rates (≥ 80% pain reduction) for overall pain were 89.5% and 68.4%, respectively, the latter up from 42.2% at 3 months. Significant improvements from baseline were observed in QOL, function, and sleep over the 24 months, including ≥ 80% experiencing a minimally important difference in QOL and > 50% experiencing a clinically significant improvement in sleep. At 24 months, 82.8% of

Pre-operative administration of BTA is a safe and effective technique in the pre-operative preparation of patients undergoing elective complex ventral hernia repair. This technique lengthens and relaxes the laterally retracted abdominal muscles and enables laparoscopic closure of large complex ventral hernia.

We investigated the incidence of and risk factors for persistent pain after caesarean delivery. Over a 12-month period, women having caesarean delivery were recruited prospectively at an Australian tertiary referral centre. Demographic, anaesthetic and surgical data were collected and at 24 hour follow-up, women were assessed for immediate postoperative pain and preoperative expectations of pain. Long-term telephone follow-up was conducted at two and 12 months postoperatively. Complete data were obtained from 426 of 469 women initially recruited (90.6%). The incidence of persistent pain at the abdominal wound at two months was 14.6% (n=62) but subsequently reduced to 4.2% (n=18) at 12 months. At two months, 33 patients (7.8%) experienced constant or daily pain. At 12 months, five patients (1.1%) continued to have constant or daily pain which was mild. There was no apparent increase in incidence of persistent pain associated with general versus regional anaesthesia (relative risk [RR] 0.89, 95% confidence interval [CI] 0.49 to 1.6); emergency vs elective procedure (RR 0.65, 95% CI 0.39 to 1.07); higher acute pain scores (RR 1.1, 95% CI 0.69 to 1.75); or history of previous caesarean delivery (RR 0.81, 95% CI 0.50 to 1.33). Persistent pain, usually of a mild nature, is reported by some women two months after their caesarean delivery, but by 12 months less than 1% of women had pain requiring analgesia or affecting mood or sleep. All declined a pain clinic review. Clinicians and patients can be reassured that caesarean delivery is unlikely to lead to severe persistent pain in the long-term.

Isoflurane impairs autoregulation of cerebral blood flow in a dose-related manner. Previous investigations in several other conditions have demonstrated that impaired autoregulation can be restored by hyperventilation. We hypothesized that hypocapnia may restore cerebral autoregulation impaired by isoflurane anesthesia. We administered isoflurane in 100% oxygen to 12 healthy patients aged 21-59 yr scheduled for elective nonneurological surgery. Isoflurane end-tidal concentration was individualized at 0.1% to 0.2% less than that required to induce short periods of isoelectric electroencephalogram. This resulted in an end-tidal isoflurane concentration of 1.6% +/- 0.2% (mean +/- sd) corresponding to an age-adjusted minimum alveolar anesthetic concentration multiple of 1.4. Mean arterial blood pressure was reduced to <80 mm Hg, by infusion of remifentanil if required. Cerebral autoregulation was assessed by infusing phenylephrine to increase mean arterial blood pressure to 100 mm Hg while monitoring middle cerebral artery blood flow velocity with transcranial Doppler ultrasonography. The change in flow velocity was used to calculate the autoregulation index (ARI). The ARI ranges between 0 and 1 and an ARI < or =0.4 indicates significantly impaired autoregulation. Autoregulation was tested twice in randomized order: once during normocapnia (Paco(2) 38-43 mm Hg) and once during hypocapnia (Paco(2) 27-34 mm Hg). The median (interquartile range) ARI was 0.29 (0.23-0.64) during normocapnia and 0.77 (0.70-0.78) during hypocapnia (P < 0.005). Of the 12 subjects, autoregulation was significantly impaired in 8 subjects during normocapnia and none during hypocapnia (P = 0.001). Hypocapnia restored cerebral autoregulation in normal subjects during isoflurane-induced impairment of autoregulation.

Our results suggest that modifying the Trendelenburg position during robot-assisted laparoscopic radical prostatectomy has a significant positive effect on patient neuro-ocular safety by lowering intraocular pressure and accelerating its recovery to the normal range without affecting the operation.