A retrospective analysis of Terlipressin infusion in patients with refractory hypotension after cardiac surgery

AIM

The aim of this retrospective study was to evaluate the effectiveness of Terlipressin in the treatment of severe hypotension in cardiosurgical patients and to assess the differences between the groups of survivors and nonsurvivors.

METHODS

The study population was 27 patients who developed hypotension after cardiac surgery.

RESULTS

All surviving patients developed refractory hypotension early after extracorporeal circulation. Of the 9 nonsurvivors, 3 also experienced postcardiotomy hypotension, while the remaining 6 developed severe hypotension during sepsis. Terlipressin given continuously significantly increased the mean arterial pressure and reduced the heart rate in both groups. Norepinephrine requirements decreased significantly among survivors only. The mean pulmonary artery pressure and pulmonary capillary wedge pressure levels remained unchanged or increased insignificantly, while several liver markers in the survivor group significantly increased.

CONCLUSION

Terlipressin given continuously is a potent vasopressor in patients with norepinephrine-resistant postcardiotomy hypotension; however, Terlipressin treatment failed in patients who developed refractory hypotension during sepsis. We cannot recommend this therapy in such patients as it proved to be hemodynamicaly ineffective and may even worsen the circulatory situation.

On-pump cardiac surgery in a conscious patient using a thoracic epidural anesthesia--an ultra fast track method

OBJECTIVE

To demonstrate the applicability and efficacy of spontaneous ventilation during cardiac surgery.

METHODS

From March 1999 through December 2002, 129 awake patients were operated on; 90 on-pump and 39 off-pump. A thoracic epidural space blockage was performed one hour prior to an incision being made at the Th 2-Th 4 level. Medial approach was used and the hanging drop method was routinely employed for epidural space detection.

RESULTS

There were 82 male and 47 female patients with a mean age of 64.5 years. Forty two cases were aortic valve replacement, 32 patients underwent on-pump coronary artery bypass grafting (CABG), 12 underwent mitral valve replacement, 27 patients were indicated for sternal wound reexploration, 12 for off-pump CABG, one for aortic valve replacement with aortic arch reconstruction and aortic valve replacement together with CABG was performed three times. There were ten conversions to general anesthesia and there was no death. Mean duration of the stay in the intensive care unit was 7.2 hours and in the hospital 5.1 days. We did not observe low cardiac output syndrome, stroke, renal insufficiency or pulmonary dysfunction in patients who sufficiently underwent thoracic epidural anesthesia. Less pain at assessments was demonstrated (Visual Analgetic Score=3.3).

CONCLUSION

The recent interest in rapid recovery and early out-patient care of patients after cardiac surgery has prompted investigations into the use of neuraxial analgesia for these procedures. The above mentioned technique would be beneficial for patients with preoperative pulmonary dysfunction and may be particularly useful in endoscopic cardiac surgery. (Tab. 1, Fig. 2, Ref. 18.)

Tracheostomy in critically ill patients

The authors made a retrospective analysis of results and complications of elective tracheostomies performed by percutaneous dilatational technique (PDT) as well as standard surgical procedure (ST) in critically ill patients in the ICU. The indication for tracheostomy was to facilitate long-term mechanical ventilation, to facilitate cleaning and management of the airway and to maintain upper airway patency. During a 5-year period there were 495 elective tracheostomies performed in the ICU setting, in 209 females and 286 males. From these, 408 were standard (82.4%) and 87 percutaneous dilatational tracheostomies (17.6%). Mean age of patients with tracheostomy was 63.3 years (range 17-93 years) and the mean duration of endotracheal intubation before tracheostomy was 7 days (range from 13 minutes to 21 days). During the monitored period 144 patients (29.0%) were decannulated, out of which 34 patients (23.6%) had PDT and 110 patients (76.4%) ST. A total of 265 patients (53.5%) with tracheostomy died and 86 patients (17.3%) had the tracheostomy cannule in place at the study conclusion. Perioperative complications totaled 14 (2.8%), the most serious being one cardiac arrest and death (0.4%) both in ST as well as in PDT groups. Early postoperative complications totaled 46 (9.2%). Late postoperative complications totaled 7 (1.4%). Percutaneous dilatational tracheostomy is an alternative method to standard surgical tracheostomy in critically ill patients in the ICUs. Standard surgical tracheostomy is an irreplaceable procedure in patients with complex anatomic condition or in high-risk patients. (Tab. 3, Ref. 11).

The potential for floral mimicry in rewardless orchids: an experimental study

More than one-third of orchid species do not provide their pollinators with either pollen or nectar rewards. Floral mimicry could explain the maintenance of these rewardless orchid species, but most rewardless orchids do not appear to have a rewarding plant that they mimic specifically. We tested the hypothesis that floral mimicry can occur through similarity based on corolla colour alone, using naive bumble-bees foraging on arrays of plants with one rewarding model species, and one rewardless putative mimic species (Dactylorhiza sambucina) which had two colour morphs. We found that when bees were inexperienced, they visited both rewardless morphs randomly. However, after bees had gained experience with the rewarding model, and it was removed from the experiment, bees resampled preferentially the rewardless morph most similar to it in corolla colour. This is the first clear evidence, to our knowledge, that pollinators could select for floral mimicry. We suggest that floral mimicry can be a selective force acting on rewardless orchids, but only under some ecological conditions. In particular, we argue that selection on early-flowering rewardless orchids that receive visits from a large pool of naive pollinators will be weakly influenced by mimicry.