Pharmacokinetics of bupivacaine after bilateral ultrasound-guided transversus abdominis plane block following cesarean delivery under spinal anesthesia.

BACKGROUND: Transversus abdominis plane block is an effective method of post-cesarean analgesia. There are no data available about plasma bupivacaine levels after this block in adults. This study aimed to assess bupivacaine pharmacokinetic parameters after ultrasound-guided transversus abdominis plane blocks following cesarean delivery under spinal anesthesia. METHODS: A prospective observational study in parturients undergoing elective cesarean delivery under hyperbaric bupivacaine spinal anesthesia was conducted. After surgery, patients received bilateral transversus abdominis plane block (50mg bupivacaine each side). Venous blood samples were collected immediately before performing the block and at 10, 20, 30, 45, 60, 90, 120, 180, 240, 720 and 1440minutes. High performance liquid chromatography was used to measure total plasma bupivacaine concentrations. Mean bupivacaine area under the curve (AUC) was calculated from 0 to 24hours. RESULTS: Data were collected from 17 parturients. Mean age and body mass index were 31±6y and 30±4kg/m2 respectively. Mean plasma bupivacaine concentration before the block was 171ng/mL. Mean peak concentration was 802.36ng/mL (range 231.8 to 3504.5ng/mL). Mean time to peak concentration was 30min and mean area-under-the-curve (0-24h) was 4505.4h.ng/mL. Mean elimination half-life was 8.75h. Three subjects had concentrations above the quoted toxic threshold and mild symptoms suggestive of neurotoxicity were reported by two subjects, but no treatment was required. CONCLUSION: Single-dose bilateral transversus abdominis plane block using 100mg of bupivacaine, after spinal anesthesia for cesarean delivery, can result in toxic plasma bupivacaine concentrations.

[Extensive Dowling-Degos disease following long term PUVA therapy]. / Maladie de Dowling-Degos étendue après PUVA thérapie prolongée.

BACKGROUND: Dowling-Degos disease is a rare and benign inherited dermatosis. PATIENTS AND METHODS: A 53-year-old woman presented with generalized histologically confirmed Dowling-Degos disease revealed 8 years after psoralen photochemotherapy (PUVA) for psoriasis. This presentation was special in terms of its considerable spread as well as the absence of comedone-like and punctate scars. DISCUSSION: Dowling-Degos disease is a reticulate pigmentary disorder of the flexures associating prominent comedone-like lesions and pitted scars. Diagnosis is based on clinical and histopathological examination, which allows this entity to be differentiated from other reticulate pigmentary disorders. A literature review failed to provide any indication that PUVA therapy either aggravates or reveals Dowling-Degos disease, a finding which we feel merits mention.