Cranioplasty for large skull defects with PMMA (Polymethylmethacrylate) or Tutoplast processed autogenic bone grafts.

OBJECTIVE: Aim of the study was a comparison of cranioplasty using the Tutoplast technology for autogenic bone processing and conventional polymethylmethacrylate (PMMA) calvarial re- construction. PATIENTS AND METHODS: A retrospective analysis was carried out in a consecutive series of 61 plastic reconstructions for skull defects, the largest measuring more than 12 cm. Cranioplasty was either performed with PMMA or with the patient's own bone graft which had been recycled using the Tutoplast process. RESULTS: 36 patients with a mean age of 44 (range 10-68) years underwent freehand PMMA cranioplasty following craniectomy for increased intracranial pressure (19 patients, 52.8%), infection (15 patients, 41.7%), or traumatic bone destruction (2 patients, 5.6%). Bilateral procedures were performed in 10 patients (27.8%). Mean follow-up was 44 months. Four patients (11.1%) died, 14 (38.9%) remained severely disabled, and 18 (50%) made a satisfactory recovery. Two patients (5.6%) had PMMA-related complications and required removal. 26 patients exhibited at least satisfactory cosmetic results (83.9%), in 5 patients the results were not satisfactory (16.1%) and in 5 the results are unknown. Twenty-five patients with a mean age of 42 (range 2-68) years received Tutoplast processed autografts following craniectomy for elevated intracranial pressure. Bilateral procedures were performed in 3 patients (12%). Mean follow-up was 15 months. One patient (4%) died, 18 (72%) remained severely disabled, and 6 (24%) made a satisfactory recovery. All patients had satisfactory cosmetic results, but 2 patients (8.3%) required removal at a later stage, one due to infection (4.2%) and one for bone resorption (4.2%). In the 18 patients with follow-up >0.5 years significant resorption occurred in all 5 children and adolescents (100%) and in two adult patients (15.4%). CONCLUSION: Cosmetic results were more satisfactory with Tutoplast processed autografts, and the operating time for unilateral surgery was shorter. Complication rates were similar. Resorption occurred in all children and adolescents, but was rare in adults. Thus, Tutoplast processed autogenic bone grafts can be a reasonable alternative to other methods of cranioplasty in adult patients with large craniotomy defects. Cranioplasty in children and adolescents remains an unsolved problem.

[The clinical significance of drug interactions between opiates and calcium antagonists. A randomized double-blind study using fentanyl and nimodipine within the framework of postoperative intravenous on-demand analgesia]. / Zur klinischen Bedeutung von Arzneimittelinteraktionen zwischen Opiaten und Kalziumantagonisten. Eine randomisierte Doppelblindstudie mit Fentanyl und Nimodipin im Rahmen der postoperativen intravenösen On-Demand Analgesie.

It is widely accepted that the nociceptive state and opiate-induced nociception are regulated at least in part by calcium ions. Animal experiments suggest that systemically or intracerebroventricularly applied calcium antagonizes analgesic effects, whereas calcium chelating agents or calcium channel blockers enhance them. Recently, von Bormann et al. [3] reported a fentanyl-saving effect in cardiovascular patients who had received an intraoperative infusion of nimodipine; this finding was discussed as a possible synergistic analgesic interaction. Since doubts remained as to whether this interpretation was justified, the present study aimed to verify, in awake postoperative patients, whether nimodipine increased the analgesic efficacy of fentanyl. Forty ASA I-II patients (mean age 43-44 years) undergoing elective hysterectomy under standardized balanced anesthesia were investigated. In the recovery room, they were allowed to self-administer fentanyl by means of the On-Demand Analgesia Computer (ODAC). Demand dose was 34.5 micrograms, infusion rate 4 micrograms/h, lockout time 1 min, hourly maximum dose 250 micrograms. The patients were randomly and double-blindly assigned to have an additional infusion of either placebo (P) or nimodipine (N: 15 micrograms/kg/h during the first 2 h, 30 micrograms/kg/h from the 3rd to the 12th h). Fentanyl consumption, pain scores (actual and retrospective), blood pressure, heart rate, respiratory rate, and side-effects were monitored. The mean duration of patient-controlled analgesia was 16 (P) to 19 (N) h, during which time 0.64 +/- 0.46 (N) to 0.79 +/- 0.43 (P) micrograms fentanyl/kg/h was demanded. Pain relief was very satisfactory in 92.5% of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Counteraction of cyanide poisoning by thiosulphate when administering sodium nitroprusside as a hypotensive treatment.

A 42-year old patient received a continuous infusion of sodium nitroprusside (SNP) at a dosage rate of 600 microgram/min for approximately four days. On the third day of treatment a dangerous high level of cyanide was measured in the blood. When an additional continuous infusion of sodium thiosulphate at five times the molar concentration of the SNP was given, this cyanide level dropped over a period of 7h to one-seventh of its initial value. The thiosulphate did not reduce the effectiveness of the SNP in lowering the blood pressure.