Verifying correct endotracheal intubation by measurement of end-tidal carbon dioxide during an ex utero intrapartum treatment procedure.

The ex utero intrapartum treatment (EXIT) procedure provides time to secure the airway of the fetus while utero-placental circulation supplies the fetus with oxygen. We report the anesthetic management of a fetus with a large neck mass during an EXIT procedure in which the confirmation of correct endotracheal intubation was hampered by parts of the mass, blood, and other fluids. The use of a standard end-tidal carbon dioxide probe provided a reliable signal and proved the endotracheal position of the tube while utero-placental circulation was still intact.

Successful reversal of deleterious coagulopathy by recombinant factor VIIa.

Effective treatment of severe or uncontrolled bleeding is a challenge for physicians in the operating room and intensive care unit. However, even aggressive conventional therapy may ultimately fail in some patients. Administration of recombinant activated factor VII (rFVIIa) may be the only remaining therapeutic option to stop life-threatening coagulopathic bleeding. We here describe the clinical course of 5 patients exhibiting severe continuous bleeding that could not be stopped by surgical intervention and appropriate hemostatic management but resolved after a mean dose of 90 microg/kg of rFVIIa (range, 90-120 microg/kg). Four of the five patients recovered completely, and one patient died after developing sepsis in multiorgan failure. In all patients, bleeding from wound surfaces stopped within minutes of the administration of rFVIIa. Coagulation measurements improved, and transfusion requirements declined considerably. No adverse effects associated with rFVIIa were observed.

Life-threatening mediastinal hematoma caused by extravascular infusion through a triple-lumen central venous catheter.

We report a case of life-threatening mediastinal hematoma in a 6-mo-old girl during surgical correction of scaphocephaly. The hematoma was caused by extravascular infusion via the proximal lumen of a dislocated triple-lumen central venous catheter (CVC). Worsening symptoms of hypovolemia and ventilation problems prompted performance of transesophageal echocardiography, which reliably and quickly allowed us to exclude pericardial tamponade and detect a mediastinal hematoma. The anesthesiologist should be alert when a patient with a CVC develops acute cardiopulmonary or respiratory symptoms. Repeated aspirations of blood, especially after major positional changes and before giving large quantities of fluid or blood, should be performed to detect secondary malposition of the CVC.

The effects of perioperatively administered crystalloids and colloids on concentrations of molecular markers of activated coagulation and fibrinolysis.

To explore whether intravenous administration of routinely used crystalloid or colloid solutions differently affects the coagulation system, we investigated orthopaedic patients. Since crystalloid solutions might cause hypercoagulability, we here present our results on molecular markers of coagulation and fibrinolysis. Patients undergoing knee replacement surgery randomly received isovolemic amounts of lactated Ringer's solution, 6% hydroxyethyl starch 200/0.5 or 4% modified gelatine. Arterial blood samples for determination of specific molecular markers of activated coagulation (thrombin/antithrombin complex, D-dimer, prothrombin fragment F1 + 2), fibrinolysis (plasmin/alpha 2-antiplasmin complex, tissue plasminogen activator, plasminogen activator inhibitor-1), and concentrations of coagulation factor XIII were obtained at baseline, before tourniquet release, at the end of surgery and 2 h after operation. During the observation period, thrombin/antithrombin complex increased from 4.8 to 54.7 microg/l, D-dimer increased from 0.3 to 6.0 mg/ml, prothrombin fragment F1 + 2 increased from 1.7 to 5.9 nmol/l, tissue plasminogen activator decreased from 7.3 to 6.7 ng/ml, plasminogen activator inhibitor-1 increased from 68.4 to 71.0 ng/ml, plasmin/alpha 2-antiplasmin complex increased from 281.5 to 884 microg/l and factor XIII decreased from 89.0 to 58.5%. All parameters changed significantly but without any detectable difference in the response profile between the groups receiving different intravenous fluids. During knee replacement surgery a pronounced activation of the coagulation/fibrinolytic system was observed, regardless of whether patients received crystalloid or colloid fluids. Thus, these results cannot confirm the hypothesis that crystalloid fluids per se cause hypercoagulability in vivo.

The effects of perioperatively administered colloids and crystalloids on primary platelet-mediated hemostasis and clot formation.

UNLABELLED: To explore whether routinely administered colloids and crystalloids influence the hemostatic system, we studied 60 patients undergoing knee replacement surgery during randomized intravascular fluid administration using 6% hydroxyethyl starch 200/0.5 (HES) or 4% modified gelatin (GEL) in addition to a basal infusion of lactated Ringer's solution (RL), or exclusively RL. In addition to routine coagulation tests, measurements of coagulation factors were performed. Also, functional measurements of the in vitro bleeding time by use of the platelet function analyzer (PFA-100 and ROTEG analysis (ROTEG(R); extrinsically and intrinsically [Ex; In] activated measurements of clotting time, CT [s]; clot formation time, CFT [s]; clot strength, A20 [mm]; fibrinogen component of the clot, FibA20 [mm]; and maximal clot elasticity) were used. Time dependency of variables was analyzed with a repeated-measures analysis of variance (all groups pooled); differences between groups were detected by comparing the calculated area under the curve (AUC(A-D)). For all variables, except ExCT, ExCFT, and InCFT, a significant time dependency was demonstrated, indicating that impaired platelet-mediated hemostasis and clot formation occurred with IV administration of fluids. Total clot strength, fibrinogen part, and clot elasticity decreased significantly more in the colloid groups than in the RL group (InA20: HES, -13.0 mm; GEL, -11.5 mm; RL, -1.3 mm; P = 0.042; FibA20: HES, -10.5 mm; GEL, -6.0 mm; RL, -1.3 mm: P < 0.0001; MCE: HES, -48; GEL, -35; RL, -15.8; P < 0.0001). The decrease in fibronectin concentrations was significantly smaller with GEL as compared with HES, whereas a weak trend toward a larger decrease in fibrinogen concentrations was observed with both colloids. Results show that colloid administration reduces final clot strength more than does RL alone, which also exhibited effects, albeit minor, on the coagulation system. The reduction in total clot strength was due to impaired fibrinogen polymerization, resulting in a decreased fibrinogen part of the clot and reduced clot elasticity. IMPLICATIONS: Our data suggest that during deliberate colloid administration, critically impaired fibrinogen polymerization and reduced fibrinogen concentrations might be reached earlier than expected. Therefore, maintaining fibrinogen concentrations seems essential when continuing blood loss is bridged by colloid infusion until transfusion triggers are reached, especially in patients already exhibiting borderline fibrinogen levels at baseline.