Extracorporeal membrane oxygenation in infants with meconium aspiration syndrome: a decade of experience with venovenous ECMO

Background

Despite the emergence of new therapies for respiratory failure of the newborn with meconium aspiration syndrome (MAS), extracorporeal membrane oxygenation (ECMO) has a significant role as a rescue modality in these infants. Our objective was to compare the use of venovenous (VV) vs venoarterial (VA) ECMO in newborns with MAS who need ECMO and to ascertain the impact of new therapies in these infants during the last decade. We also evaluated how disease severity or time of ECMO initiation affected mortality and morbidity.

Methods

A report of 12 years experience (1990-2002) of a single center, comparing VV and VA ECMO, is given. Venovenous ECMO was the preferred rescue modality for respiratory failure unresponsive to maximal medical therapy. Venoarterial ECMO was used only when the placement of a VV ECMO 14-F catheter was not possible; 128 patients met ECMO criteria, 114 were treated with VV ECMO, and 12 with VA ECMO. Two patients were converted from VV to VA ECMO.

Results

Venovenous and VA ECMO patients had comparable birth weight (mean ± SEM, 3.48 ± 0.05 vs 3.35 ± 0.15 kg) and gestational age (40.3 ± 0.1 vs 40.7 ± 0.3 weeks). Before ECMO, there was no difference between VV and VA ECMO patients in oxygenation index (60 ± 3 vs 63 ± 8), mean airway pressure (19.5 ± 0.4 vs 20.8 ± 1.5 cm H₂O), alveolar-arterial O₂ gradient (630 ± 2 vs 632 ± 4 torr), ECMO cannulation age (median [25th-75th percentiles], 23 [14-47] vs 26 [14-123] hours), or in the % of patients who needed vasopressors/inotropes (98% vs 100%). From November 1994, inhaled nitric oxide (NO) was available. Before VV ECMO, 67% of the patients received NO, 24% received surfactant, and 48% were treated with high-frequency ventilation (HFV). There was no significant difference between VV and VA ECMO patients in survival rate (94% vs 92%), ECMO duration (88 [64-116] vs 94 [55-130] hours), time of extubation (9 [7-11] vs 14 [9-15] days), age at discharge (23 [18-30] vs 27 [15-41] days), or incidence of short-term intracranial complications (5.3% vs 16.7%). For the total cohort of 126 infants, indices of disease severity (oxygenation index, alveolar-arterial O₂ gradient, mean airway pressure) did not correlate with outcome measures. Delay in ECMO initiation (>96 hours) was associated with prolonged mechanical ventilation and hospitalization (P < .01). New therapies (NO, HFV, surfactant) in the second part of the decade were associated with a longer ECMO duration (98 [80-131] vs 87 [60-116] hours; P < .05), no delay in ECMO initiation time (23 [10-40] vs 24 [14-52] hours), and no significant change in survival (97% vs 92.5%). No patient was treated with VA ECMO after 1994.

Conclusions

Venovenous ECMO is as reliable as VA ECMO in newborns with MAS in severe respiratory failure who need ECMO. Delay in ECMO initiation may result in prolonged mechanical ventilation and increased length of hospital stay. The emergence of new conventional therapies (NO, HFV, surfactant) and particularly increased experience enable sole use of VV ECMO with no significant change in survival in infants with MAS.     

Thimerosal – Is it really irrelevant?

Recently, several investigators claimed that thimerosal is one of the most irrelevant allergens existing in screening for contact dermatitis. 508 patients who were suspected to have allergic contact dermatitis were patch tested at our clinic. They completed a questionnaire including medical, demographic and occupational details. We used the standard tray of chemotechnique diagnostics (Malmö, Sweden) and additional series, which were case relevant. The relevance of the allergic reaction to thimerosal was scored from 1 to 6. 19 patients (3.7%) had an allergic reaction to thimerosal. 6 (31.5%) had a definite relevance and 8 (42.1%) had a probable relevance. Only 3 patients (15.8%) had an irrelevant reaction. SPIN value (significance–prevalence index number) was 2281. We found a high proportion of mechanics (42.1%) among the patients who had positive reaction to thimerosal (P < 0.0001). Although previous reports found thimerosal highly irrelevant, our daily experience being supported by the above data indicates that positive reactions to thimerosal could be relevant for many patients.     

Synthesis and evaluation of oxazaborolidines for antibacterial activity against Streptococcus mutans

Several representative oxazaborolidines have been synthesized and evaluated against S. mutans for antibacterial activity. This is the first reported antibacterial activity of this class of compounds. The minimal inhibitory concentration values ranged from 0.53 to 6.75 mM.     

Coping with trauma: narrative and cognitive perspectives

The immediate period following a traumatic event is a crucial time in the survivors' process of recovery. During this time, a narrative of the trauma is generated and constructed, alongside a process of cognitive processing of the traumatic events. In the first part of the article we present the outlines of the narrative and cognitive attitudes to trauma; the second part will illustrate the developmental process through which the trauma narrative is shaped, in the stories of five survivors of a terror attack. We suggest that by analyzing three main components of the trauma narrative (coherence, finding meaning and self-evaluation), together with the equivalent cognitive attitudes, it is possible to evaluate the process of recovery, identify foci of difficulties in this process and pinpoint possible therapeutic interventions in the early stages after the trauma.     

How accurate are neonatologists in identifying clinical jaundice in newborns?

This study reevaluates the clinical ability to accurately identifyjaundice in neonates. Three hundred seventy-one term infants were clinically asseseed forjaundice, before discharge home on day 2 to 3 of life. Bilirubin levels obtained at the same time were significantly higher in the newborns clinically diagnosed as beingjaundiced. Our neonatologists were able to diagnose jaundice at clinically low levels, and not to misdiagnose significant hyperbilirubinemia in the majority of the infants. The trained human eye can still discriminate between the jaundiced and nonjaundiced newborn, and clinical impression of jaundice remains a reliable primary screening tool for significant neonatal hyperbilirubinemia.     

Laparoscopic cyst decortication in autosomal dominant polycystic kidney disease: impact on pain,hypertension, and renal function

BACKGROUND AND PURPOSE: In patients with autosomal dominant polycystic kidney disease (ADPKD), laparoscopic cyst decortication (LCD) has been proposed as a means to relieve chronic cyst-related pain. We present our 7-year experience with LCD for ADPKD with regard to pain relief, hypertension, and renal function. PATIENTS AND METHODS: Between August 1994 and February 2001, 29 ADPKD patients with chronic pain (N=29), hypertension (N=21), and renal insufficiency (N=10) underwent 35 LCD procedures. Every detectable cyst within 2 mm of the renal surface was treated. Pain relief was assessed using a pain analog scale; relative pain relief (RPR) equaled (preoperative pain score) - (postoperative pain score)/(preoperative pain score). Hypertension was evaluated using the antihypertensive therapeutic index (ATI): [(dose of blood pressure medication 1/max dose 1) + (dose med 2/max dose 2) + etc.] x 10. Renal function was assessed using the Cockcroft and Gault formula for creatinine clearance. RESULTS: The mean operating room time was 4.9 hours (range 2.6-6.6 hours) with no conversions to open surgery. An average of 220 cysts (range 4-692) were treated per patient. The mean follow-up was 32.3 months (range 6-72 months). The RPR was 58%, 47%, and 63% at 12, 24, and 36 months, respectively. At 12, 24, and 36 months, 73%, 52%, and 81% of patients, respectively, noted >50% improvement in their pain compared with the preoperative situation. Five patients became normotensive, and patients improved their ATI by an average of 49% (range 11%-93%). However, six patients had worsening hypertension, with an ATI increase averaging 53% (range 11%-122%), and one patient who was not hypertensive preoperatively has since developed hypertension. The creatinine clearance changed +4%, +7%, and -2% at 12, 24, and 36 months, respectively. Only one patient had a >20% increase in creatinine clearance. The only patients with a >20% decrease in creatinine clearance were those who had a creatinine clearance <30 mg/dL preoperatively (average decrease 34% [range 20%-51%]). CONCLUSIONS: For ADPKD patients with debilitating pain, extensive LCD can provide durable relief. In the majority of patients with pain and hypertension, a marked improvement in blood pressure also occurs. Cyst decortication was not associated with worsening renal function; indeed, renal function remained largely unchanged over the 3-year follow-up period.     

Laparoscopic ileocytoplasty and continent ileovesicostomy in a porcine model

BACKGROUND AND PURPOSE: Bladder augmentation with autologous bowel is commonly accompanied by a continent ileovesicostomy (the Monti procedure). Herein, we describe our initial experience with laparoscopy-assisted ileocystoplasty and continent ileovesicostomy in a porcine model. MATERIALS AND METHODS: Thirteen Yucatan minipigs with an average weight 49 lb underwent a laparoscopy-assisted ileocystoplasty and ileovesicostomy (Monti procedure) using a four-port technique. After catheter removal at 3 weeks, the animals underwent twice-daily catheterization of the ileovesicostomy until complete occlusion of the ileovesicostomy occurred. RESULTS: All animals survived the initial surgery, with 10 animals being available for catheterization at 3 weeks. The average Monti anastomotic time, average ileal patch-bladder anastomotic time, and average total surgery times were 47 minutes, 89 minutes, and 307 minutes, respectively. Eight of ten animals developed stomal stenosis after catheter removal (average time to complete occlusion of 6 days; range 1-13 days), with two animals also demonstrating partial obstruction at the Monti-bladder anastomosis and four partial obstruction at the fascial level of the Monti tube. Pathologic review of select bladder augmentation and Monti tube specimens revealed moderate to severe acute and chronic inflammation with severe scarring at the Monti-skin stoma site in the majority of specimens. CONCLUSIONS: We have demonstrated the feasibility of laparoscopic ileocystoplasty and continent ileovesicostomy in a porcine model. The development of stomal stenosis may be related to the intrinsic properties of the pig skin, but additional investigation is required prior to human studies of this novel surgical technique.