Merrill McHoney

Effect of Patient Weight and Anesthetic Technique on CO2 Excretion During Thoracoscopy in Children Assessed by End-Tidal CO2

AIM The aim of this study was to review the changes in CO(2) excretion and anesthetic management during thoracoscopy in children. METHODS We analyzed end-tidal carbon dioxide concentration (EtCO(2); kPa) during CO(2) pneumothorax. EtCO(2) was measured on a continuous basis by using a positive sampling system and recorded every 10 minutes. Baseline and highest EtCO(2) were used to derive the maximum change in the intraoperative period. EtCO(2) was also analyzed in three time periods: (1) preinsufflation, (2) during insufflation of CO(2) into the chest, and (3) after desufflation. Core temperature was also recorded as an index of thermoregulation. Data are presented as the mean +/- standard error of the mean. Differences within time periods were compared by using paired t tests or repeated measures analysis of variance. Correlation between changes in EtCO(2) and patient demographics was performed by using linear regression. The pattern of change was compared to children undergoing laparoscopy. RESULTS Median age was 1.9 years (range, 1 day to 15 years). EtCO(2) increased significantly from preinsufflation 5.1 +/- 0.2 to 6.4 +/- 0.3 during insufflation (P < 0.01); values were still significantly elevated after desufflation 6.4 +/- 0.4 (P < 0.01). Single-lung ventilation was associated with higher EtCO(2) levels during insufflation than with two-lung ventilation (P = 0.02). Maximum change in the EtCO(2) in the group undergoing one-lung ventilation negatively correlated to patient weight (r(2) = 0.25, P = 0.02); this correlation was not present with two-lung ventilation (r(2) = 0.02, P = 0.84). Laparoscopy increased EtCO(2) from 4.7 +/- 0.2 preinsufflation to 5.3 +/- 0.2 (P < 0.001) during and decreased to 4.8 +/- 0.2 postdesufflation (P = 0.60). There was a significant increase in core temperature from 35.9 +/- 0.3 to 36.9 +/- 0.2 postoperatively (P = 0.007). CONCLUSIONS There is a significant increase in EtCO(2) in children undergoing thoracoscopy, which is higher than during laparoscopy. Changes in EtCO(2) are larger in smaller children undergoing single-lung ventilation. Thoracoscopy may preserve intraoperative thermoregulation.

Congenital diaphragmatic hernia, management in the newborn

Congenital diaphragmatic hernia (CDH) in the newborn poses challenges to the multi-disciplinary teams involved in its management. Mortality remains significantly high, despite growing understanding and treatment options. Early intubation of antenatally diagnosed cases is crucial in preventing deterioration and persistent pulmonary hypertension. Early recognition of cases not diagnosed on antenatal scan, with appreciation of differential diagnosis, requires an index of suspicion and imaging. Increasing options and modalities are available, with only modest, if any, survival advantage. Permissive hypercapnea and minimal ventilation have made the most significant impact on survival in modern era. High-frequency oscillatory ventilation (HFOV), inhaled nitric oxide (iNO), treatment of pulmonary hypertension, and ECMO are used in a somewhat stepwise manner for stabilisation. Delayed surgery has become established later in management plan. The impact of individual therapies (e.g. HFOV, iNO, ECMO) on outcome is difficult to ascertain. Little level 1 or 2 evidence exists. Randomised studies and reviews on the role of ECMO have not yet proven any long-term survival benefit. One pilot randomised study of thoracoscopic repair suggests increased acidosis; intraoperative blood gases and CO2 levels should be closely monitored. Monitoring tissue oxygenation should be considered. There is no evidence to suggest the best patch material.

Congenital diaphragmatic hernia

There is a paucity of level 1 and level 2 evidence for best practice in surgical management of CDH. Antenatal imaging and prognostication is developing. Observed to expected lung-to-head ratio on ultrasound allows better predictive value over simple lung-to-head ratio. Based on 2 randomised studies, the verdict is still out in terms the best group and indication for antenatal intervention and their outcome. Tracheal occlusion is best suited for prospective randomised studies of benefit and outcome. Only one pilot randomised controlled study of thoracoscopic repair exists, suggesting increased acidosis; blood gases and CO2 levels should be closely monitored. Only poorly controlled retrospective studies suggest higher recurrence rates. Randomised studies on the outcome of thoracoscopic repair are needed. Careful selection, anaesthetic vigilance, monitoring and follow-up of these cases are required. There is no evidence to suggest the best patch material to decrease recurrences. Evidence suggests no benefit from routine fundoplication based on the one randomised study. Multi-disciplinary follow-up is required. This can be visits to different specialities, but may be best served by a multi-disciplinary one-stop clinic.

Early human development: Neonatal tumours: Vascular tumours

Vascular tumours (haemangiomas and malformations) are common tumours of infancy and childhood. They represent a group of mostly benign conditions, which present early, can grow rapidly and be symptomatic or disfiguring. There are various management options, with different cosmetic and functional outcomes. Haemangiomas and vascular malformations have different clinical courses which dictate respective management; differentiating them is key. Haemangiomas are generally self-limiting after initial proliferation; generally management is conservative. Symptoms can call for treatment. Options include laser, steroids, chemotherapy and surgery. Propanolol, the newest modality of treatment, may have a dramatic effect in problematic lesions. Vascular malformations are a less common group of heterogenous lesions, with some overlap between entities. They do not involute. Treatment options include laser therapy, sclerotherapy, embolisation, and surgery. Emerging therapies include photodynamic therapy and angiogenesis inhibitors. This review will outline the evidence for the various modalities in managing these conditions.

Role of ECMO in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is typified morphologically by failure of diaphragmatic development with accompanying lung hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). Patients who have labile physiology and low preductal saturations despite optimal ventilatory and inotropic support may be considered for extracorporeal membrane oxygenation (ECMO). Systematic reviews into the benefits of ECMO in CDH concluded that any benefit is unclear. Few randomised trials exist to demonstrate clear benefit and guide management. However, ECMO may have its uses in those that have reversibility of their respiratory disease. A few centres and networks have demonstrated an increase in survival rate by post hoc analysis (based on a difference in referral patterns with the availability of ECMO) in their series. One issue may be that of careful patient selection with regard to reversibility of pathophysiology. At present, there is no single test or prognostication that predicts reversibility of PPHN and criteria for referral for ECMO is undergoing continued refinement. Overall survival is similar between cannulation modes. There is no consensus on the time limit for ECMO runs. The optimal timing of surgery for patients on ECMO is difficult to definitively establish, but it seems that repair at an early stage (with careful perioperative management) is becoming less of a taboo, and may improve outcome and help with either coming off ECMO or decisions on withdrawal later. The provision of ECMO will continue to be evaluated, and prospective randomised trial are needed to help answer question of patient selection and management.

Simple Purse String Laparoscopic Versus Open Hernia Repair

AIMS To compare surgical outcomes for a simple purse string method of laparoscopic hernia (LH) repair with a traditional open inguinal hernia (OH) repair in children in a single center. MATERIALS AND METHODS Following ethical approval, a retrospective review of all children undergoing LH repair from January 2010 to December 2013 versus a historic cohort of all OH repairs between January 2010 and December 2011 was conducted. LH repair was performed by a simple purse string technique using nonabsorbable braided suture. Groups were compared using the independent t test or the Mann-Whitney test as appropriate. RESULTS One hundred three patients (23 females, 80 males) underwent LH repair over the 4-year period compared with 151 (25 females, 126 males) OH procedures in the first 2 years. Median age in the LH group was 0.56 years (range, 0.04-14.7 years) compared with 0.52 years (range, 0.04-13.47 years) in the OH group (P = .81). In the LH group the intended operation was bilateral in 18 (17.4%); 85 were clinically unilateral, but at operation a contralateral patent processus vaginalis was repaired in 26 (30.5%). Median operative time was 50.5 minutes (range, 20-95 minutes) in the LH group and 20 minutes (range, 10-90 minutes) in the OH cohort (P < .0001). Recurrence rate was 2.9% in the LH group and 3.9% in the OH group, and overall complication rates were 7.8% and 9.9%, respectively. CONCLUSIONS LH repair yields similar results to OH repair; however, the operation time is significantly longer. All complication rates were statistically similar on balance. Almost one-third of LH procedures resulted in concurrent detection and repair of a contralateral patent processus vaginalis at laparoscopy.

Esophageal Atresia and Tracheoesophageal Fistula

Thoracoscopic repair of esophageal atresia (OA) and tracheoesophageal fistula (TOF) is one of the most advanced and technically demanding minimally invasive surgery (MIS) operations in pediatric surgery. Since the first report by Rothenberg and Lobe in 1999 [1], there has been much investment in the development of this operation. There remains much debate about the benefits and risks of the thoracoscopic approach compared with those of open surgery. Nevertheless it is now performed by those with sufficiently advanced MIS skills with good outcomes.

Thoracoscopic Debridement of Empyema

The incidence of postpneumonic empyema has been increasing in recent years in most Western countries. The place of surgery in its management is debatable, with many centers advocating initial pleural drainage and instillation of fibrinolytics, reserving surgery for those who fail to respond to these measures. Some, however, suggest that primary surgery leads to a more rapid recovery and a shorter hospital stay. There is little evidence to convincingly show which is the best approach. The aim of surgery is clearance of debris from the pleural space, with reestablishment of a “single” pleural cavity free of loculations and full reexpansion of the lung. Postoperatively, early mobilization and physiotherapy are key. Thoracoscopy has the advantage of excellent visualization of the whole pleural space and minimal postoperative pain, allowing physiotherapy and mobilization to begin almost immediately.

Inguinal Hernia Repair

Potential advantages of the laparoscopic approach to inguinal hernias in children include avoiding handling of the vas and vessels in boys, inspection of the internal genital organs in girls, and diagnosis of asymptomatic contralateral hernia. In experienced hands, the recurrence rate is minimal and approaches that of open surgery. It may be an advantageous approach to incarcerated hernias.

Introduction and General Principles

Minimally invasive surgery (MIS) has become relatively commonplace in paediatric surgery, and is becoming more popular. Paediatric surgeons perform laparoscopic and thoracoscopic surgery with the commonly held belief that MIS is associated with a dampened stress response, more rapid postoperative recovery, and early discharge from hospital. There are also long-term cosmetic advantages. Depending on the operation in question, some of the potential advantages hold, but others do not, and we need to be conscious of potential disadvantages and difficulties when embarking on MIS.