[Hypoxaemia during non-intubated adenotonsillectomy; more common in sitting or supine position?] / Hypoxemie bij adenotonsillectomie zonder intubatie: vaker in liggende of zittende operatiehouding?

OBJECTIVE: To investigate the incidence of hypoxaemia, bradycardia and post-operative bleeding in non-intubated Sluder method adenotonsillectomy patients in sitting versus supine position. DESIGN: Explorative study. METHOD: A retrospective database was drawn up with data from all patients on whom a Sluder method non-intubated adenotonsillectomy was performed in a Dutch district general hospital between 01 January 2012 and 01 May 2018. Depending on the preference of the surgeon and following discussion with the anaesthesiologist, the operation was performed with the patient in either a sitting or supine position. The primary outcome measure was hypoxaemia, defined as SpO2 < 85% for ≥ 60 seconds. Secondary outcome measures included bradycardia and post-operative bleeding. RESULTS: We analysed the data of 723 adenotonsillectomy patients (46% female, average age 4.5 years), of whom 193 (27%) in sitting and 530 (73%) in supine position. Hypoxaemia occurred in 13 (7%) 'sitting' cohort patients and in 13 (2%) of the supine cohort patients (p = 0.011). No perioperative complications developed as a result of the hypoxaemia. The frequency of bradycardia did not differ between the two cohorts (4 vs 2%; p = 0.442). None of the patients developed both hypoxaemia and bradycardia. In 8 (1%) patients, a secondary intervention was required due to the occurrence of post-operative haemorrhage. CONCLUSION: Patients who undergo non-intubated Sluder guillotine method adenotonsillectomy when in a sitting position are more likely to develop hypoxaemia than those who are operated on in a supine position. In order to make an informed recommendation, a randomized trial is indicated.

A randomized, dose-response study of sugammadex given for the reversal of deep rocuronium- or vecuronium-induced neuromuscular blockade under sevoflurane anesthesia.

BACKGROUND: Sugammadex is the first of a new class of selective muscle relaxant binding drugs developed for the rapid and complete reversal of neuromuscular blockade induced by rocuronium and vecuronium. Many studies have demonstrated a dose-response relationship with sugammadex for reversal of neuromuscular blockade in patients induced and maintained under propofol anesthesia. However, sevoflurane anesthesia, unlike propofol, can prolong the effect of neuromuscular blocking drugs (NMBDs) such as rocuronium and vecuronium. METHODS: We designed this randomized, open-label, dose-response trial to explore the dose-response relationship of sugammadex for the reversal of deep neuromuscular blockade induced by rocuronium or vecuronium under propofol-induced and sevoflurane-maintained anesthesia. As a secondary objective, the safety variables of sugammadex were evaluated. After anesthesia induction with propofol, 102 patients aged > or = 20 and < 65 yr were randomized to receive a single bolus dose of rocuronium 0.9 mg/kg (n = 50) or vecuronium 0.1 mg/kg (n = 52), followed by maintenance doses (rocuronium 0.1-0.2 mg/kg or vecuronium 0.02-0.03 mg/kg) as needed. Neuromuscular blockade was monitored using acceleromyography. After the last dose of NMBD, at 1-2 posttetanic counts, a single bolus dose of sugammadex 0.5, 1.0, 2.0, 4.0, or 8.0 mg/kg was administered. The primary efficacy variable was time from start of sugammadex administration to recovery of the T(4)/T(1) ratio to 0.9. RESULTS: The per-protocol population consisted of 48 patients in the rocuronium group and 47 in the vecuronium group. A dose-response effect was demonstrated for decreased mean time to recovery of the T(4)/T(1) ratio to 0.9 with increasing sugammadex dose in both NMBD groups (per-protocol population): rocuronium group, 79.8 (SD 33.0) min (sugammadex 0.5 mg/kg) to 1.7 (0.7) min (4.0 mg/kg) and 1.1 (0.3) min (8.0 mg/kg subgroup); vecuronium group, 68.4 (31.9) min (0.5 mg/kg) to 3.3 (3.5) min (4.0 mg/kg), and 1.7 (0.8) min (8.0 mg/kg subgroup). Neuromuscular monitoring showed recurrent neuromuscular blockade in 5 patients, all in the rocuronium group (2 given sugammadex 0.5 mg/kg and 3 given 1.0 mg/kg), but there were no clinical events attributable to recurrent or residual neuromuscular blockade. CONCLUSION: Sugammadex at doses of > or = 4 mg/kg provides rapid reversal of deep rocuronium- and vecuronium-induced neuromuscular blockade under sevoflurane maintenance anesthesia.

Long-term epidural block treatment in patients with early threatening preterm delivery and vaginal fetal engagement.

We report on an exceptional therapy with epidural anesthesia and tunnelling of the peridural catheter over a time period of 2-14 days in patients with threatening early preterm labor, intact membranes and vaginal engagement of the infants (4 singleton, 8 twin and 2 triplet pregnancies). A combination of bupivacaine (0.125%) and fentanyl (2 microg/mL) was used up to a maximum of 20 mL/h during the treatment period. Long-term follow-up of the infants was normal in 19/20 infants. The advantages, such as prolongation of pregnancy without maternal pain and disadvantages such as the risk of fetal and maternal infection and of sudden delivery are discussed. The online version of the Journal (see http://dx.doi.org/10.1515/jpm.2008.081_supp-1) allows video illustrations of a triplet pregnancy, in which the first triplet was born after one week of epidural anesthesia and the pregnancy continued under epidural anesthesia for the remaining two triplets staying with intact membranes in the vagina (delayed interval delivery) for six more days. The results of this pilot series suggest that prolongation of these pregnancies under epidural anesthesia might be an option in exceptional cases when viability is questionable or when corticosteroid therapy is desired before final delivery. Further evaluation of this strategy is needed but only in tertiary centers with 24-h presence of qualified obstetric and neonatal care and intensive surveillance.

A temporary decrease in twitch response during reversal of rocuronium-induced muscle relaxation with a small dose of sugammadex.

BACKGROUND: We present a case in which a temporary decrease in train-of-four (TOF) response was observed after reversal of muscle relaxation with a small dose (0.5 mg/kg) of sugammadex administered 42 min after 0.9 mg/kg of rocuronium. At the end of the operation, the TOF ratio was >0.9, and the patient woke normally, without signs of muscle weakness. We describe this temporary decrease in muscle response during muscle relaxation reversal as muscle relaxation rebound and hypothesize that it occurs when the dose of sugammadex is sufficient for complex formation with rocuronium in the central compartment, but insufficient for redistribution of rocuronium from peripheral to central compartments. METHODS: To investigate our hypothesis, we developed and fit a simple pharmacokinetic- pharmacodynamic model of rocuronium, sugammadex, and their interaction to the patient TOF response data. RESULTS: Simulations using the fitted model indicate that muscle relaxation rebound can occur for doses of sugammadex in a limited critical range. CONCLUSIONS: Sufficiently large doses of sugammadex eliminate the possibility for muscle relaxation rebound, which does not require dissociation of the sugammadex/ rocuronium complex.

Anatomical and pathological considerations in percutaneous vertebroplasty and kyphoplasty: a reappraisal of the vertebral venous system.

OBJECTIVES: To focus attention of the clinician on the anatomy and (patho)physiology of the vertebral venous system, so as to offer a tool to better understand and anticipate (potential) complications that are related to the application of percutaneous vertebroplasty and kyphoplasty. BACKGROUND: Percutaneous vertebroplasty and kyphoplasty are newly developed, minimally invasive techniques for the relief of pain and for the strengthening of bone in vertebral body lesions. With the clinical implementation of these techniques, a number of serious neurologic and cardiopulmonary complications have been reported in the international medical literature. Most complications appear to be related to the extrusion of bone cement into the vertebral venous system. METHODS: The literature about complications of percutaneous vertebroplasty and kyphoplasty is reviewed, and the anatomic and (patho)physiologic characteristics of the vertebral venous system are reported. Based on what is currently known from the anatomy and physiology of the vertebral venous system, the procedures of percutaneous vertebroplasty and kyphoplasty are analyzed, and suggestions are made to improve the safety of these techniques. CONCLUSIONS: Thorough knowledge of the anatomic and (patho)physiologic characteristics of the vertebral venous system is mandatory for all physicians that participate in percutaneous vertebroplasty and kyphoplasty. To reduce the risk of cement extrusion into the vertebral venous system during injection, vertebral venous pressure should be increased during surgery. This can be achieved by operating the patient in the prone position and by raising intrathoracic venous pressure with the aid of the anesthesiologist during intravertebral instrumentation and cement injection. Intensive theoretical and practical training, critical patient selection, and careful monitoring of the procedures, also taking into account patient positioning and intrathoracic and intra-abdominal pressures, will help to facilitate low morbidity outcomes in these very promising minimally invasive techniques.