Long-term haematological response and maintained immunological function after laparoscopic subtotal splenectomy in patients with hereditary spherocytosis.

INTRODUCTION: Subtotal or total splenectomy are recommended in severe and should be considered in intermediate forms of hereditary spherocytosis (HS). Data on laparoscopic subtotal splenectomy (LSTS) in HS patients are sparse. METHODS: Thirty three patients with HS (median age 10.7 years (yrs), range 1.8-15.5) underwent LSTS. Baseline and follow-up investigation included haematological parameters, microscopic analysis of pitted erythrocytes (pitE), and B-cell subpopulations assessed by flow cytometry. Results were compared to those of non-splenectomised HS patients, HS patients after total splenectomy (TS), and healthy individuals. RESULTS: After LSTS, haemoglobin levels were normalised in all patients. During median long-term follow-up of 3.9 yrs (range 1.1-14.9), only four patients presented mild anaemia. Despite re-growing of the remnant spleen none of the patients required a second surgical intervention. As compared to TS, PitE in LSTS patients were significantly lower and indicated normal to only moderately decreased spleen function. Relative but not absolute IgM memory B-cell counts were reduced in both LSTS and TS patients. CONCLUSIONS: LSTS is effective for the treatment of patients with HS. A small remnant spleen is sufficient to provide adequate phagocytic function and to induce a pool of IgM memory B-cells.

The effect of intermittent intraabdominal pressure elevations and low cardiac output on the femoral to carotid arterial blood pressure difference in piglets.

BACKGROUND: Our previous work in a laparoscopic setting in piglets revealed that the systolic femoral artery pressure was approximately 5 % higher than its carotid counterpart, whereas the mean and diastolic values showed no significant difference. This remained idem when the intraabdominal pressure (IAP) was gradually increased. In this study, we aimed to investigate the effect of (1) intermittent IAP elevations and (2) a low cardiac output (CO) on the blood pressure (BP) difference cranially (carotid artery) and caudally (femoral artery) of a capnoperitoneum (ΔP = P a fem-P a carot). METHODS: A total of twenty-two piglets (mean body weight 11.0 kg; range 8.9-13.3 kg) were studied. Of these, 14 underwent intermittent IAP elevations at 8 and 16 mmHg, and ΔP was measured. In another 8 piglets, a model of reduced CO was created by introducing an air embolism (2 ml/kg over 30 s) in the inferior caval vein (VCI) at 12 mmHg IAP to further assess the influence of this variable on ΔP. RESULTS: Systolic ΔP remained at a mean of 5.6 mmHg and was not significantly affected by insufflation or exsufflation up to an IAP of 16 mmHg. Diastolic and mean values showed no differences between P a carot and P a fem. P a fem, systol remained higher than its carotid counterpart as long as the cardiac index (CI) was above 1.5 l/min/m2, but fell significantly below P a carot, systol at a low CI. There was no CO-dependent effect on diastolic and mean ΔP. Repeated IAP elevations do not significantly influence ΔP. CONCLUSIONS: Intermittent IAP elevations do not significantly influence ΔP. Despite of a CO-dependent inversion of systolic ΔP, mean BP measurements at the leg during laparoscopy remain representative even at low CO values.

Air in the insufflation tube may cause fatal embolizations in laparoscopic surgery: an animal study.

BACKGROUND: The aim of this study was to evaluate the risk of an air embolization with the volume of the insufflation tube during induction of laparoscopy. A further objective was to determine the LD50 of air in young piglets. METHODS: End-tidal carbon dioxide pressure ([Formula: see text]), pulmonary arterial pressure (P pa), heart rate (f c), and mean arterial pressure (P a carot) were measured in 17 piglets divided into three groups: group 1 (n = 6), bolus application (CO2 embolization, followed by air embolization, 2 mL/kg each), group 2 (n = 7), continuous air embolization (30 min, 0.2 mL/kg/min), and group 3 (n = 4), continuous CO2 embolization (30 min, 0.4 mL/kg/min). RESULTS: All animals survived CO2 embolism. Air embolization as a bolus (2 mL/kg) or with an accumulated volume of 3.1 mL/kg led to death. Decreases in [Formula: see text] indicated air or massive CO2 embolization only. There was a good correlation between [Formula: see text] and P pa in case of air embolization (r = -0.80, p < 0.0001). In contrast, no dependency was recognized during CO2 embolism (r = -0.17, p = 0.2). CONCLUSIONS: In order to minimize the lethal risk of gas embolization, the insufflation system has to be completely filled with CO2 before connecting to the patient.

Embolism risk analysis--helium versus carbon dioxide.

BACKGROUND: Helium is used as an insufflation gas to avoid the negative properties of carbon dioxide (CO(2)), such as CO(2) accumulation, acidosis, and tachycardia, particularly in the case of insufficient respiratory function, seen also in infancy. Any laparoscopic procedure carries the risk of a gas embolism. MATERIALS AND METHODS: Seven anesthetized piglets (weighing 9.9-12.8 kg), randomized into three groups, served as models for pre-teenage children. Three piglets received a CO(2) embolism, followed by a helium embolism of 2 mL/kg, respectively. Helium was administered to three piglets, whereas both gases were repeatedly administered alternately to one piglet. The embolisms were administered for 30 seconds via a central venous line. Cardiac output was measured using the thermodilution method. The observation period for each embolism was 60 minutes in Groups 1 and 2 and 15 minutes in Group 3. RESULTS: All animals survived CO(2) embolisms. Four of the six piglets died after helium embolisms. Following helium embolisms there was a prompt initial decrease in the end-tidal CO(2) pressure and an initial increase in the pulmonary arterial pressure. A further decrease in arterial blood pressure was prevented by a compensatory increase in the heart rate and appeared just before death. After only 5 minutes cardiac output showed a 25% decline from the initial value. Helium embolisms led to a severe increase in the pulmonary dead space. CONCLUSIONS: Embolisms with the smallest amounts of helium administered via direct venous puncture have an immediate lethal impact. Extended perioperative monitoring and trocar placement under vision should be performed.