Dexmedetomidine attenuates the hemodynamic and neuroendocrinal responses to skull-pin head-holder application during craniotomy

We tested dexmedetomidine, an alpha2 agonist, for its ability to decrease heart rate, arterial blood pressure, and neuroendocrinal responses to skull-pin head-holder application during craniotomy. In a randomized, double-blinded, placebo-controlled study, 40 patients undergoing craniotomy with attachment of a pin head-holder were randomly assigned to one of 2 equal groups. The placebo group received saline, whereas the treatment group (DEX group) received a single bolus dose of dexmedetomidine (1 microg/kg) intravenously over 10 minutes before induction of anesthesia. Arterial blood pressure, heart rate, and sequential concentrations of circulating cortisol, prolactin, insulin, and blood glucose were measured. Relative to baseline and the other group, arterial blood pressure and heart rate decreased significantly after the administration of dexmedetomidine through skull pinning (P<0.05). In the placebo group, patients' heart rate and arterial blood pressure measures increased at 1 and 5 minutes after skull-pin insertion, compared with baseline and the DEX group (P<0.05). In both groups, plasma cortisol, prolactin, and blood glucose increased significantly relative to baseline after skull-pin insertion. However, the values were significantly higher in the placebo group compared with the DEX group (P<0.05). Although insulin levels were not significantly altered in the DEX group, the plasma concentrations of insulin decreased significantly after pin insertion in the placebo group. Our results suggested that, a single bolus dose of dexmedetomidine before induction of anesthesia attenuated the hemodynamic and neuroendocrinal responses to skull-pin insertion in patients undergoing craniotomy.     

Fabrication of Thermally Crosslinked Hydrolyzed Polymers of Intrinsic Microporosity (HPIM)/Polybenzoxazine Electrospun Nanofibrous Membranes

In this study, thermally crosslinked hydrolyzed polymers of intrinsic microporosity (HPIM)/polybenzoxazine electrospun nanofibrous membranes (NFMs) are successfully produced. The nanofibers having 800 ± 260 to 670 ± 150 nm average fiber diameters from HPIM and blends of HPIM/ benzoxazine (BA‐a) ranging from HPIM:(BA‐a) weight ratio of 9:1 to 2:1 w/w are produced by electrospinning. Self‐standing HPIM/(BA‐a) NFMs are thermally step‐wise cured resulting in crosslinked HPIM/Poly(BA‐a) NFMs. Structural characterization of as‐electrospun HPIM/(BA‐a) and crosslinked HPIM/Poly(BA‐a) NFM is conducted by FT‐IR spectroscopy to trace the ring opening and crosslinking reactions. Elemental analysis and XPS studies show an increase in carbon content and reduction in nitrogen content due to the crosslinking reaction. Decomposition temperature (T _d) of HPIM NFM increases from 218 to 270 °C with the crosslinking based on the DSC. DMA analysis shows that the mechanical strength of the NFMs has increased significantly with crosslinking. Young's moduli of HPIM NFM is increased from 16 ± 7 to 67 ± 1 MPa for crosslinked HPIM/Poly(BA‐a)%33 NFM. Similarly, higher storage modulus is observed for HPIM/Poly(BA‐a) NFMs compared to HPIM NFM. The crosslinked HPIM/Poly(BA‐a) NFMs keep their fibrous morphology after solvent treatment in dimethylformamide revealing their structural stability compared to pristine HPIM NFM.     

Renal functions in obstructive sleep apnea patients

Sleep and Breathing -     

Migration of an intrauterine contraceptive device to the sigmoid colon: a case report.

BACKGROUND: Copper T intrauterine devices (IUDs) remain the mainstay of family planning measures in developing countries, but have been associated with serious complications such as bleeding, perforation and migration to adjacent organs or omentum. Although perforation of the uterus by an IUD is not uncommon, migration to the sigmoid colon is extremely rare. Here, we report a case of migration of an IUD to the sigmoid colon. CASE REPORT: A 40-year-old woman who had an IUD (Copper T), inserted 1 month after delivery, presented, 7 months later, with secondary amenorrhea and transient pelvic cramps. Clinical findings and ultrasonographic examinations of the patient revealed an 8-week pregnancy, while laboratory tests were normal. Transvaginal ultrasonography also visualized the IUD located outside the uterus, near the sigmoid colon, as if it were attached to the bowel. The pregnancy was terminated at the patient's wish; a diagnostic laparoscopy was performed concomitantly, which showed bowel perforation owing to the migration of the IUD. The device, which was partially embedded in the sigmoid colon, was removed via laparoscopy; however, because of bowel perforation, laparotomy was performed to open colostomy. CONCLUSIONS: This case report highlights the continuing need for intra- and postinsertion vigilance, since even recent advances in IUD technique and technology do not guarantee risk-free insertion.     

Assessment of fetal cerebral arterial and venous blood flow before and after vaginal delivery or Cesarean section.

OBJECTIVES: To compare perinatal intracranial arterial and venous blood velocity changes between healthy term neonates delivered vaginally or by Cesarean section and to correlate these changes with cord blood gases and pH values at birth. METHODS: The study involved 43 healthy term neonates who were delivered vaginally (n = 20) or by Cesarean section (n = 23). All fetuses/neonates were examined by Doppler ultrasound to obtain middle cerebral artery (MCA) and cerebral transverse sinus (Tsin) Doppler waveforms on three occasions (before delivery, and 1 h and 24 h after birth). Pulsatility index (PI) and peak systolic velocity (PSV) for MCA and Tsin were measured and compared between neonates who were delivered vaginally or by Cesarean section. Umbilical cord blood samples were analyzed for umbilical artery and vein pH, pO(2) and pCO(2) and values were correlated with MCA and Tsin Doppler indices. RESULTS: MCA-PI increased and MCA-PSV decreased at 1 h after birth, and Doppler measurements returned to predelivery values at 24 h after birth. Tsin Doppler measurements remained unchanged at 1 h and 24 h when compared to predelivery values in both the Cesarean and vaginal delivery groups. There was a negative correlation between Tsin-PI before birth and umbilical venous pH. There was a positive correlation between Tsin-PSV at 1 h after birth and umbilical vein pCO(2). CONCLUSIONS: Cerebral arterial blood velocity decreases immediately after birth and increases within 24 h, probably as part of neonatal adaptation. Cerebral venous blood velocity remains constant during the perinatal period and is likely to be regulated in a different and more complex manner than that of arterial blood velocity. Mode of delivery does not affect cerebral blood velocity.     

Subclinical infections with Crimean-Congo hemorrhagic fever virus, Turkey

To investigate Crimean-Congo hemorrhagic fever virus in Turkey, we conducted a seroepidemiologic survey during January-April 2009. Seroprevalence of infection was 10% in a sample from an outbreak region and increased with patient age, indicating that the virus had been previously present in Turkey. We also estimated that 88% of infections were subclinical.