Cannula Diameter Research Articles

Impairment of Venous Drainage Due to Atrial Septal Aneurysm During Open-Heart Surgery

IT IS NOT UNCOMMON to encounter inadequate venous drainage during cardiopulmonary bypass. Some common causes include poor positioning and obstruction of the venous cannula, increased resistance due to the small diameter of the venous cannula, and kinks in the tubing that connects the venous cannula to the venous reservoir. We report a case of atrial septal aneurysm (ASA) impairing venous drainage from a 2-stage venous cannula in right atrium during a routine cardiac surgery case requiring cardiopulmonary bypass (CPB). Intraoperative transesophageal echocardiogram (TEE) was instrumental in diagnosis and treatment of the decreased venous drainage.

Absorbable gelatin plug does not prevent iatrogenic preterm premature rupture of membranes after fetoscopic laser surgery for twin–twin transfusion syndrome

Despite fetoscopic laser ablation (FLA) having emerged as an effective treatment for twin-twin transfusion syndrome (TTTS), major postintervention challenges, such as iatrogenic preterm premature rupture of membranes (iPPROM), remain. A chorioamniotic plug (CAP) made of absorbable gelatin sponge has been used to seal the trocar entry site in the chorioamniotic layers to promote healing and prevent iPPROM, yet the results have been equivocal. Our objective was to test the hypothesis that, following FLA for TTTS, iPPROM may be prevented by placement of an absorbable gelatin CAP. A retrospective cohort study was performed on prospectively collected data from 134 consecutive patients who underwent FLA for TTTS. The decision for CAP placement was at the discretion of the physician. Preoperative, operative and postoperative variables were collected and analyzed. The primary outcome was the incidence of iPPROM, and the secondary outcomes were procedure-to-delivery interval and gestational age at delivery. Comparative statistical analysis was performed as appropriate. A CAP was placed in 72 (54%) of 134 patients. Factors significantly associated with CAP placement were higher gravidity (P = 0.03), anterior placentation (P = 0.04), general endotracheal intubation (P = 0.02) and a cannula diameter of 12-Fr (P = 0.003). There were no differences between CAP and no-CAP groups in the rate of iPPROM (39% vs 34%, respectively; P = 0.42) or in the procedure-to-delivery interval (65.3 ± 34.7 days vs 58.2 ± 30.8 days, respectively; P = 0.21). The gestational age at delivery was later in the CAP group compared with the no-CAP group (30.7 ± 4.5 weeks vs 28.9 ± 3.9 weeks, respectively; P = 0.02). CAP did not reduce the overall risk for iPPROM and did not increase the procedure-to-delivery interval. Further research is needed to identify other methods to prevent iPPROM and prolong pregnancy after laser therapy.

Avalon© Bicaval Dual-Lumen Cannula for Venovenous Extracorporeal Membrane Oxygenation

We conducted an epidemiologic survey in France on the use of bicaval dual-lumen cannulas for extracorporeal membrane oxygenation (ECMO). Every service that used the Avalon cannula was contacted. Practitioners answered questions concerning its practical usage and complications that were attributable to its usage. We report data for 52 instances of cannula usage. The primary indication was acute respiratory distress syndrome (ARDS) in 77% of cases. Of all of the patients who required cannulas, 46% died. The maximum flow was 2,175 ± 556 ml/minute for 20-Fr.-diameter cannulas, 3,207 ± 653 ml/minute for 23 Fr., 3,963 ± 729 ml/minute for 27 Fr., and 5,490 ± 984 ml/minute for 31 Fr. Surgeons placed the cannulas in 52% of cases, intensivists placed the cannulas in 23% of cases, and multidisciplinary teams placed the cannulas in 25% of cases. The mean insertion time was 26 ± 13 minutes, and insertion was performed under transesophageal electrocardiography (TEE) (67%), transthoracic echocardiography (TTE) (25%), fluoroscopy (4%), or no guidance (4%). The main complication was migration into the right ventricle. Problems with hemolysis were described in 21% of cases. No case of cannula thrombosis was found. No case of infection was reported. Bleeding was noted in 17% of cases. The mean time of use was 8 ± 7 days. Modifications to the supportive care system were required in 15% of cases. Monitoring was performed by chest x-rays (90%), TTE (42%), and TEE (46%). Five extubations occurred during the support period. Nine patients were mobilized. The use of this cannula yielded satisfactory results. We suggest placing these cannulas using TTE or TEE and recommend the use of large-caliber cannulas in hypoxemic patients.

445: Maternal diet alters the offspring microbial gene catalogue as revealed by whole genome shotgun (WGS) sequencing in a primate model of obesity

catalogue as revealed by whole genome shotgun (WGS) sequencing in a primate model of obesity Radhika Ganu, Jun Ma, Antonio Frias, Diana Takahashi, Joseph Petrosino, Kevin Grove, James Versalovic, Kjersti Aagaard Baylor College of Medicine, Division of Maternal-Fetal Medicine, and Departments of Obstetrics and Gynecology, Molecular and Cell Biology, and the Bioinformatics Research Lab, Houston, TX, Oregon Health & Science University, Obstetrics and Gynecology, Portland, OR, Oregon Health & Science University, Oregon National Primate Research Center, Beaverton, OR, Baylor College of Medicine, Molecular Virology and Microbiology, Houston, TX, Baylor College of Medicine and Texas Children’s Hospital, Pathology & Immunology, Houston, TX OBJECTIVE: The infants microbiome (totality of microorganisms) is felt to be relatively sparse at birth. Based upon mode of delivery, gestational age, and breastfeeding it is thereafter variably populated. We have previously employed 16S-based metagenomics in our well-characterized primate model of maternal obesity, and observed that maternal diet additionally structures the offsprings microbiome. However, clear delineation of which species and microbial genes are influenced by the maternal diet has heretofor eluded us. Our study objective was to employ WGS metagenomics with metabolic pathway reconstruction to delineate not only which microbes are (or are not) present, but what these microbes are capable of doing. STUDY DESIGN: Age and weight-matched dams on control (13%) or HF (35%) diet yielded two distinct maternal cohorts emerged: obese HF diet sensitive [HFS] & lean HF resistant [HFR]. Based on the 16S-based analysis of over 200 comprehensive body site samples collected to date (placenta, oral, GI, fecal, GU) limited (n 12) samples for costly massively parallel WGS sequencing on the Illumina HiSeq (panel A). Binned microbial sequences were analyzed using MetaPhlAn (taxonomy abundance) and HuMAnN (pathway reconstruction). Significant features differentiating the groups were identified and ranked by Z-score corresponding to p-value. RESULTS: Consistent with maturation of the primate gut microbiome over the first year of life, maternal and juvenile gut microbiomes are distinguishable (Panel B). Juvenile gut microbiomes and associated metabolic pathways are significantly structured primarily by virtue of maternal diet, with a lesser contribution by maternal obesity (Panels C & D). CONCLUSION: High resolution metagenomics supports the notion that a highfat maternal diet in utero structures the offspring gut microbiome to 1 year of age; these are accompanied by significant alterations in bacterial metabolic gene catalogues. 446 Predictors of preterm delivery (PTD) after fetoscopic laser surgery (FLS) for twin twin transfusion syndrome (TTTS) Ramesha Papanna, Lovepreet Mann, Dana Block-Abraham, Irina Buhimschi, Michael Bebbington, Elisa Garcia, Nahla Khalek, Christopher Harman, Kenneth Moise Jr., Ahmet Baschat, Anthony Johnson Yale University, Ob/Gyn & Reprod. Sci., New Haven, CT, University of Maryland School of Medicine, Obstetrics, Gynecology and Reproductive Sciences, Baltimore, MD, University of Texas Health Science Center, Obstetrics, Gynecology and Reproductive Sciences, Houston, TX, The Children’s Hospital of Philadelphia, The Center for Fetal Diagnosis and Treatment, Philadelphia, PA OBJECTIVE: Despite the success of FLS for TTTS, PTD remains a critical contributor to adverse outcome. There is a paucity of data to explain the possible causes for PTD after FLS. Our objective is to identify the risk factors associated with preterm delivery after FLS. STUDY DESIGN: Prospectively collected data from 4 US fetal centers of 495 patients was centralized to an independent research center. Exclusion criteria were triplet pregnancies (n 24) and selective reduction for a failed FLS (n 12). Periand post-operative variables were collected and analyzed. Subgroups were created based on the median gestational age at delivery of 32 weeks (mean SD: 31.2 4.9w). Risk factors and outcomes were compared between these groups. Comparative statistics were performed using appropriate statistical analysis (statistical significance p 0.05). Multivariate logistic regression was performed on the significant factors on univariate analysis. RESULTS: Significant comparisons are shown in Table 1. There were no differences in peri-operative variables. On multivariate analysis, greater maternal age at procedure, iPPROM (occurring in 32%).and larger cannula diameter increased the risk for early PTD. iPPROM reduced the procedure to delivery interval by 22 days (Kaplan-Meier survival analysis; p 0.001) and the associated rate for 9,10 and 12 Fr cannulas were 16%, 30%,42%, respectively, and procedure-to-delivery intervals (days) were 83.4 34.6, 79.3 36, and 59.6 36.8, respectively (all 0.001). Pre-viable ( 24 weeks) delivery occurred in 10%, and was attributable to iPPROM in 30% and spontaneous preterm labor in 57%. CONCLUSION: Early preterm delivery remains a major complication of FLS. Cannulas size and the associated rate of iPPROM appear to be the significant contributors to preterm birth. Further research should focus on methods to prevent iPPROM and to improve instrumentation to decrease the size of the cannula and maintain better visualization during fetoscopy. Poster Session III Doppler Assess, Fetus, Prematurity, U/S, Med-Surg-Diseases www.AJOG.org

Frameless multimodal image guidance of localized convection-enhanced delivery of therapeutics in the brain

IntroductionConvection-enhanced delivery (CED) has been shown to be an effective method of administering macromolecular compounds into the brain that are unable to cross the blood-brain barrier. Because the administration is...

Assessment of Right Pump Outflow Banding and Speed Changes on Pulmonary Hemodynamics During Biventricular Support With Two Rotary Left Ventricular Assist Devices

The absence of an effective, easily implantable right ventricular assist device (RVAD) significantly diminishes long-term treatment options for patients with biventricular heart failure. The implantation of a second rotary left ventricular assist device (LVAD) for right heart support is therefore being considered; however, this approach exhibits technical challenges when adapting current devices to produce the lower pressures required of the pulmonary circulation. Hemodynamic adaptation may be achieved by either reducing the rotational speed of the right pump impeller or reducing the diameter of the right outflow cannula by the placement of a restricting band; however, the optimal value and influence of changes to each parameter are not well understood. Hemodynamics were therefore investigated using different banding diameters of the right outflow cannula (3-6.5 mm) and pump speeds (500-4500 rpm), using two identical rotary blood pumps coupled to a pulsatile mock circulation loop. Reducing the speed of the right pump from 4900 rpm (for left ventricle support) to 3500 rpm, or banding the Ø10 mm (area 78.5 mm²) right outflow graft to Ø5.4 mm (22.9 mm²) produced suitable hemodynamics. Pulmonary pressures were most sensitive to banding diameters, especially when RVAD flow exceeded LVAD flow. This occurred between Ø5.3 and Ø6.5 mm (22.05-38.5 mm²) and speeds between 3200 and 4400 rpm, with the flow imbalance potentially leading to pulmonary congestion. Total flow was not affected by banding diameters and speeds below this range, and only increased slightly at higher values. Both right outflow banding or right pump speed reduction were found to be effective techniques to allow a rotary LVAD to be used directly for right heart support. However, the observed sensitivity to diameter and speed indicate that challenges may be presented when setting appropriate values for each patient, and control over these parameters is desirable.

Laparoscopy Rein and a Backward Needle Entrance

Since the awakening of single-port laparoscopy and culdolaparoscopy and with the increased interest in minilaparoscopy-assisted natural orifice surgery and pure natural orifice peritoneoscopy, laparoscopists are in pursuit of techniques with less percutaneous assistance. We made a rein using a 6-cm straight cutting edge needle in a 2-0 nylon suture with a large clip tied near the end as stoppage. We are also presenting an optional technique of placing the 6-cm straight needle backward, when the diameter of the cannula does not allow the parallel passage of the needle holder. The rein is simple, inexpensive, and easy to assemble, and may solve some problems of traction and triangulation without additional ports.

Extraction of urethral calculi by transabdominal cystoscopy and urethroscopy in nine dogs

To describe a minimally invasive technique for treating urethral obstructions in male dogs and to review the postoperative results. All dogs (n=9) had urethral obstruction due to calculi. Obstructions were verified by radiographic and ultrasonographic examinations. Dogs with impaired kidney function were not included in the study. A 5-mm diameter trocar and cannula were placed in the ventral midline, 2 cm cranial to the umbilicus, allowing placement of a 10-mm diameter cannula under visual guidance, adjacent to the apex of the bladder. The bladder was then partially exteriorised and sutured to the skin. A 5-mm diameter cystoscopy sheath was introduced into the bladder lumen and advanced into the urethra. Continuous retrograde flushing was used to dislodge the calculi from the site of obstruction and collect them upstream. The nine dogs were followed up for a minimum of 6 months. No major postoperative complications were identified. One dog exhibited transient macroscopic haematuria (for 3 weeks postoperatively). All urethral calculi were removed in the nine dogs. No recurrence was found during the follow-up period. A minimally invasive approach is used to treat urethral obstructions resulting from calculi in the male dogs.

Curved Root Canals: Effects of Dimensional Parameters on the Insertion Depth of Irrigation Needles

Objective: To investigate the effects of size and taper of the apical preparation, root canal curvature and cannula diameter on the insertion depth of irrigation cannulas into root canals. Study Design: One hundred and four root canals were divided into four curvature groups (0-5°; 6°-15°; 16°-25°; >25°). After apical enlargement to size 25.06 a 25G and a 30G irrigation cannula were inserted until binding. The distance between the cannula tip and the working length was related to the root canal length. The insertion procedure was repeated after enlargement to 40.04. Results: In curved canals (>6°), the cannula never reached WL. With an apical preparation of 40.04 the 30G cannula could be introduced nearly to WL even in moderately curved canals (<26°). Conclusion: Only a 30G cannula allows delivery of the irrigant to the apex of a curved root canal. The cannula could be inserted closer to WL when the apical preparation size was wider with a smaller taper compared to a small apical preparation size with a wider taper.

Characterization of Precurved Needles for Use in Distal Tip Manipulation Mechanisms

Precurved needles are used in a variety of medical applications for both passive and active control of instrument position. In one application, the deployment of a precurved stylet from a concentric outer cannula can be used to achieve lateral positioning of the distal tip of the stylet. This paper outlines how the material and geometry of the stylet can be chosen to ensure that it will not yield and thus repeatedly return to its precurved shape when deployed from a cannula. Using this methodology, we calculate the maximum strain for a range of stylet geometries and show that nitinol is required for the stylet material so that it will not plastically deform. Then, 16 stylets of varying diameters (0.508 mm, 0.635 mm, 0.838 mm, and 0.990 mm) and radii of curvature (10 mm, 20 mm, 30 mm, and 40 mm) were manufactured. Experiments were performed with four different diameter cannulas (20, 18, 16, and 14 gauges) to measure the forces required to deploy the stylets from and retract them back inside the cannulas. Retraction forces were measured between 0.3 N and 13.9 N, and deployment forces were measured between 0.2 N and 7.0 N. For a given cannula, it was found that force increases as the stylet diameter increases and as the bend radius decreases.

Comparison of different methods of ventilation via cannula cricothyroidotomy in a trachea–lung model

Cannula cricothyroidotomy is recommended in recent guidelines as a rescue intervention in the 'cannot-intubate cannot-ventilate' scenario. Several methods of providing ventilation via a cannula cricothyroidotomy have been described, but there are no data comparing these methods and using cannulae of differing diameters.Using a bench-top trachea-lung model (comprising a Siemens test lung attached to commercially available breathing system tubing), we compared delivered minute volumes (MVs) for five methods of ventilation administered through cannulae of diameters 20, 16, 14, and 13 G. The ventilation methods were: an ENK oxygen flow modulator, a Manujet, a self-inflating resuscitation bag, the oxygen flush of an anaesthetic machine, and oxygen from a wall-mounted flow meter attached via a three-way tap to the cannula. All experiments were performed with and without a proximal 2.5 mm diameter constriction to simulate partial upper airway obstruction.MVs increased with increasing cannula diameter. In the absence of a proximal constriction, MVs delivered via a 20 G cannula were <1 litre min(-1) with all devices; only the Manujet delivered MVs >2 litre min(-1), at cannula sizes of >or=16 G. MVs were greater in the presence of a proximal constriction, but did not exceed 4 litre min(-1) using the low-pressure devices.Extrapolated to the clinical situation, these data suggest that low-pressure devices will not deliver adequate MVs via a cannula cricothroidotomy and should no longer be advocated. Purpose-made devices should be available in all areas where anaesthesia is administered or airway interventions are performed.

OP09.08: Rate of amniorrhexis is not affected by fetoscopic access cannula diameter

OP09.08: Rate of amniorrhexis is not affected by fetoscopic access cannula diameter

508: Rate of amniorrhexis is not affected by fetoscopic access cannula diameter

508: Rate of amniorrhexis is not affected by fetoscopic access cannula diameter

New bench test for venous cannula performance assessment

Cannula design is of prime importance for venous drainage during cardiopulmonary bypass (CPB). To evaluate cannulas intended for CPB, an in vitro circuit was set up with silicone tubing between the test cannula encased in a movable preload reservoir and another static reservoir. The pressure-drop (DeltaP) value (P-drainage - P-preload) was measured using Millar pressure transducers. Flow rate (Q) was measured using an ultrasound flowmeter. Data display and data recording were controlled using a LabView application, custom made particularly for our experiments. Our results demonstrated that DeltaP, Q, and cannula resistance (DeltaP/Q) values were significantly decreased when the cannula diameter was increased for Smart and Medtronic cannulas. Smartcanula showed 36% and 43% less resistance compared to Medtronic venous and Medtronic femoral cannulas, respectively. The cannula shape (straight- or curved-tips) did not affect the DLP cannula resistance. Out of five cannulas tested, the Smartcanula outperforms the other commercially available cannulas. The mean (DeltaP/Q) values were 3.3 +/- 0.08, 4.07 +/- 0.08, 5.58 +/- 0.10, 5.74 +/- 0.15, and 6.45 +/- 0.15 for Smart, Medtronic, Edwards, Sarns, and Gambro cannulas, respectively (two-way ANOVA, p < 0.0001). In conclusion, the present assay allows discrimination between different forms of cannula with high or low lumen resistance.

Correlation Between Peripheral and Central Venous Pressures in Children with Congenital Heart Disease

Central venous pressure (CVP) measurement is a reliable method for evaluating intravascular volume status and cardiac function, but it is an invasive method that results in some complications such as arterial puncture, pneumothorax, and development of infection. The current study was performed to compare CVP measurements between central and peripheral catheters in infants and children with congenital heart disease referred for right-sided heart catheterization. The CVP and peripheral venous pressure (PVP) in 45 patients were measured simultaneously. The mean difference between CVPs measured from the central and peripheral catheters was 8 +/- 4 cm H(2)O. The linear regression equation showed that CVP = 0.32 PVP + 3.8 (r = 0.67; p < 0.005). There was no difference in CVP measurements depending on the intravenous cannula and chest diameters, arm diameter, arm length, body surface area, patient's age (< or =10 years and >10 years), and type of congenital heart disease (cyanotic or noncyanotic). In conclusion, although CVP measured from a peripheral intravenous catheter in infants and children with congenital heart disease is not as accurate as the measurement in adults, the aforementioned linear regression equation based on measurement of PVP gives a reliable estimate of CVP.

Histologic evaluation of laser lipolysis: pulsed 1064-nm Nd:YAG laser versus cw 980-nm diode laser

The use of the laser as an auxiliary tool has refined the traditional technique for lipoplasty. During laser lipolysis, the interaction between the laser and the fat produced direct cellular destruction before the suction, reduced bleeding, and promoted skin tightening. This study sought to perform a comparative histologic evaluation of laser lipolysis with the pulsed 1064-nm Nd:YAG laser versus a continuous 980-nm diode laser. A pulsed 1064-nm Nd:YAG (Smart-Lipo; Deka, Italy) and a CW 980-nm diode laser (Pharaon, Osyris, France) were evaluated at different energy settings for lipolysis on the thighs of a fresh cadaver. The lasers were coupled to a 600-microm optical fiber inserted in a 1-mm diameter cannula. Biopsy specimens were taken on irradiated and non-irradiated areas. Hematoxylin-erythrosin-safran staining and immunostaining (anti-PS100 polyclonal antibody) were performed to identify fat tissue damage. In the absence of laser exposures (control specimens), cavities created by cannulation were seen; adipocytes were round in appearance and not deflated. At low energy settings, tumescent adipocytes were observed. At higher energy settings, cytoplasmic retraction, disruption of membranes, and heat-coagulated collagen fibers were noted; coagulated blood cells were also present. For the highest energy settings, carbonization of fat tissue involving fibers and membranes was clearly seen. For equivalent energy settings, 1064-nm and 980-nm wavelengths gave similar histologic results. Laser lipolysis is a relatively new technique that is still under development. Our histologic findings suggest several positive benefits of the laser, including skin retraction and a reduction in intraoperative bleeding. The interaction of the laser with the tissue is similar at 980 nm and 1064 nm with the same energy settings. Because higher volumes of fat are removed with higher total energy, a high-power 980-nm diode laser could offer an interesting alternative to the 1064-nm Nd:YAG laser.

Variability in tracheostomy tubes

Our unit performs approximately 50 percutaneous tracheostomies per year to aid in weaning of patients from mechanical ventilation. Having recently changed our choice of tracheostomy tubes from Shiley (Tyco Healthcare UK Ltd, Gosport, UK) to Portex Blue Line Ultra (Smiths Medical International Ltd, Hythe, UK) we noted that our patients took longer to wean. On closer examination of the two types of size 8 tubes we noted several significant differences. The Shiley size 8 tracheostomy tube has an internal diameter of 9 mm and the inner cannula has an internal diameter of 8 mm. The corresponding measurements for the Portex tubes are 8 mm and 6.5 mm, respectively (Fig. 2). The corresponding measurements for the Tracoe Twist (Tracoe Medical GmbH, Frankfurt, Germany) are shown in Table 1. Left-to-right: Portex size 8 tracheostomy tube, Portex inner cannula, Shiley inner cannula, Shiley size 8 tracheostomy tube. Having noted the difference in the internal diameters of the two tracheostomy tubes we thought there might also be a similar difference with the external diameters, which would have implications for the ease of percutaneous insertion and size of defect in the trachea. There is, however, a 0.3-mm difference between the two (Table 1). The Tracoe has the smallest outer diameter, 11.4 mm, yet it has an inner cannula with an internal diameter of 8 mm. The largest printed figure on the packet of the Portex tube relates to the inner diameter of the tracheostomy tube only and we feel that this is a source of confusion, as the corresponding figure on the Shiley tube relates to the inner diameter of the inner cannula. As a result of these findings our unit has now changed back to using Shiley tracheostomy tubes when performing percutaneous tracheostomies, and we are considering using the Tracoe as it has the most desirable dimensions.

The role of cannula diameter in improved adipocyte viability: A quantitative analysis

Fat injection for soft tissue augmentation is a common procedure in plastic surgery. Because the limitation of fat injection is its resorption, understanding how different handling techniques affect adipocyte survival is crucial to optimizing long-term results. In this study; we sought to determine the effect of aspiration and injection cannula diameters on adipocyte viability. Fat aspiration samples were obtained from 6 female patients undergoing abdominoplasty. Viable adipocytes were counted at fat suspension, which was obtained with 2-, 3-, and 4-mm-diameter aspiration cannulas and injected with 1.6-, 2-, and 2.5-mm-diameter injection cannulas. A greater number of viable adipocytes were detected using a 4-mm-diameter aspiration cannula (419 x 10(4) cell/1 mL, P < .05) and a 2.5-mm-diameter injection cannula (410 x 10(4) cell/1 mL, P < .05). The use of wider-diameter cannulas can potentially improve fat graft survival and reduce fat graft resorption.

Systemic leakage during isolated limb perfusion for melanoma.

A hazard of regional perfusion for melanoma is incomplete isolation, resulting in leakage of the cytostatic drug into the systemic circulation. Data were analysed retrospectively on 438 melphalan perfusions performed for melanoma of the extremities during the period 1978-1990; continuous isotopic measurement of systemic leakage was carried out. The cumulative systemic leakage after 60 min perfusion was 0.9 per cent (95 per cent confidence interval 0.7-1.1 per cent). Systemic leakage of > or = 1 per cent was detected in 12.6 per cent of perfusions, > or = 5 per cent in 6.2 per cent and > or = 10 per cent in 1.4 per cent. In 2.3 per cent of patients, systemic side-effects in the form of mild transient bone marrow depression occurred. Six variables related to the perfusion technique were assessed by multivariate analysis for their influence on systemic leakage. The level of isolation and diameter of the venous cannula emerged as significant factors. In addition, ligation of the internal iliac vein provided optimal isolation during iliac perfusion.

Foetal surgery and cleft lip and palate: current status and new perspectives

Now-a-days, high-resolution ultrasound allows an accurate and relatively early diagnosis of congenital malformations. In a limited number of such conditions foetal surgery may be lifesaving. However, premature labour has been the major drawback for open foetal surgery. Recently, improvement of video-endoscopic technology has boosted the development of operative techniques for feto-endoscopic surgery, which has been demonstrated to be less invasive than the open approach. Main clinical application of fetoscopic procedures today is the treatment of feto-foetal transfusion syndrome. Although still in development, feto-endoscopic surgery seems to offer new hope for surgical foetal therapy not only in cases of life threatening conditions. Experimental intrauterine correction of cleft lip and palate (CLP) has been lately performed using the feto-endoscopic approach. This procedure offers two major advantages: first, scarless foetal wound healing and bone healing without callus formation, which would also allow a better/normal maxillary growth, and second, significant decrease of foetal and maternal morbidity. Herein, we report the current status of experimental and clinical foetal surgery and propose possible directions for continuing research to make intrauterine procedures safer. Furthermore, we discuss current knowledge and new perspectives of experimental foetal cleft lip and palate repair, which in the future may lead to such excellent results in the operative treatment of clefts, that less or no secondary corrections and therapies, such as orthodontic, dental, logopedic, etc. would be needed. Only if these conditions can be fulfilled, will we be able to improve substantially our therapy for the human foetus with a cleft lip and palate. In spite of all efforts, however, it must be considered that it may not ever be possible to find the optimal treatment method for this or other craniofacial malformations.