Combined Usage of Inhaled and Intravenous Milrinone in Pulmonary Hypertension after Heart Valve Surgery

Secondary pulmonary hypertension is a frequent condition after heart valve surgery. It may significantly complicate the perioperative management and increase patients’ morbidity and mortality. The treatment has not been yet completely defined principally because of lack of the selectivity of drugs for the pulmonary vasculature. The usage of inhaled milrinone could be the possible therapeutic option. Inodilator milrinone is commonly used intravenously for patients with pulmonary hypertension and ventricular dysfunction in cardiac surgery. The decrease in systemic vascular resistance frequently necessitates concomitant use of norepinephrine. Pulmonary vasodilators might be more effective and also devoid of potentially dangerous systemic side effects if applied by inhalation, thus acting predominantly on pulmonary circulation. There are only few reports of inhaled milrinone usage in adult post cardiac surgical patients. We reported 2 patients with severe pulmonary hypertension after valve surgery. Because of desperate clinical situation, we decided to use the combination of inhaled and intravenous milrinone. Inhaled milrinone was delivered by means of pneumatic medication nebulizer dissolved with saline in final concentration of 0.5 mg/ml. The nebulizer was attached to the inspiratory limb of the ventilator circuit, just before the Y-piece. We obtained satisfactory reduction in mean pulmonary artery pressure in both patients, and they were successfully extubated and discharged. Although it is a very small sample of patients, we conclude that the combination of inhaled and intravenous milrinone could be an effective treatment of secondary pulmonary hypertension in high-risk cardiac valve surgery patient. The exact indications for inhaled milrinone usage, optimal concentrations for this route, and the beginning and duration of treatment are yet to be determined

Intracoronary administration of levosimendan in patients with acute coronary syndromes and decreased left ventricular ejection fraction undergoing coronary artery bypass graft surgery

In cardiac surgery patients, intracoronary (IC) administration of levosimendan can provide optimal drug spread, enabling effective manifestation of favorable drug effects and avoiding potentially harmful systemic hypotension. This could be beneficial in acute coronary syndromes (ACS) with decreased left ventricular ejection fraction (LVEF). We present ten cases of IC administration of levosimendan in ACS manifested as ST segment elevation myocardial infarction, non-ST segment elevation myocardial infarction or unstable angina pectoris. All patients underwent coronary artery bypass graft (CABG) surgery, performed as an “off-pump” or “onpump”/“ off-clamp” procedure (latter one with the use of cardiopulmonary bypass on the beating heart). Levosimendan was administered as an IC bolus (125-250 μg) in each coronary artery graft (2-3 grafts). Intravenous (IV) levosimendan infusion continued (0.1-0.2 μg•kg-1•min-1) after graft placements (24-48 h), with IV infusion of norepinephrine (0.1 mg•ml-1), if needed. Cardiac function was assessed using LVEF (%) (Teicholz), thermodilution cardiac index (CI) (ml•m-2), and systemic vascular resistance (SVR) (dynes•sec•cm-5). Nonparametric Wilcoxon signed-ranks test [presented as median (MED) with interquartile range (IQR)] indicated a significant difference between preoperative vs. immediate postoperative CI, SVR, and LVEF in all cases [2.2 (1.9-2.5) vs. 3.1 (2.9- 3.4) ml•m-2, 1173.0 (1062.7-1278.2) vs. 882.5 (763.5-993.0) dynes•sec•cm-5, 44.5 (36.0-46.7) vs. 53.5 (45.7-59.2) %, respectively] (P=0.005), i.e. IC administration of levosimendan was associated with prompt improvement of intraoperative hemodynamics and cardiac contractility. IC administration of levosimendan may be a promising alternative method for improving decreased cardiac function in acute cardiac ischemia, besides necessary surgical revascularization

Ventilation inhibits sympathetic action potential recruitment even during severe chemoreflex stress

© 2017 the American Physiological Society. This study investigated the influence of ventilation on sympathetic action potential (AP) discharge patterns during varying levels of high chemoreflex stress. In seven trained breath-hold divers (age 33 ± 12 yr), we measured muscle sympathetic nerve activity (MSNA) at baseline, during preparatory rebreathing (RBR), and during 1) functional residual capacity apnea (FRCApnea) and 2) continued RBR. Data from RBR were analyzed at matched (i.e., to FRCApnea) hemoglobin saturation (HbSat) levels (RBRMatched) or more severe levels (RBREnd). A third protocol compared alternating periods (30 s) of FRC and RBR (FRC-RBRALT). Subjects continued each protocol until 85% volitional tolerance. AP patterns in MSNA (i.e., providing the true neural content of each sympathetic burst) were studied using wavelet-based methodology. First, for similar levels of chemoreflex stress (both HbSat: 71 ± 6%; P = NS), RBRMatched was associated with reduced AP frequency and APs per burst compared with FRCApnea (both P _ 0.001). When APs were binned according to peak-to-peak amplitude (i.e., into clusters), total AP clusters increased during FRCApnea (+10 ± 2; P \u3c 0.001) but not during RBRMatched (+1 ± 2; P = NS). Second, despite more severe chemoreflex stress during RBREnd (Hb-Sat: 56 ± 13 vs. 71 ± 6%; P = 0.001), RBREnd was associated with a restrained increase in the APs per burst (FRCApnea: +18 ± 7; RBREnd: +11 ± 5) and total AP clusters (FRCApnea: +10 ± 2; RBREnd: +6 ± 4) (both P \u3c 0.01). During FRC-RBRALT, all periods of FRC elicited sympathetic AP recruitment (all P \u3c 0.001), whereas all periods of RBR were associated with complete withdrawal of AP recruitment (all P = NS). Presently, we demonstrate that ventilation per se restrains and/or inhibits sympathetic axonal recruitment during high, and even extreme, chemoreflex stress. NEW & NOTEWORTHY The current study demonstrates that the sympathetic neural recruitment patterns observed during chemoreflex activation induced by rebreathing or apnea are restrained and/or inhibited by the act of ventilation per se, despite similar, or even greater, levels of severe chemoreflex stress. Therefore, ventilation modulates not only the timing of sympathetic bursts but also the within-burst axonal recruitment normally observed during progressive chemoreflex stress

Chemoreceptor threshold for the onset of involuntary respiratory movements during maximal apnea

Potreba za disanjem tijekom zadržavanja daha rezultira nastankom nevoljnih dišnih pokreta. Ovom se studijom željelo utvrditi pokreću li IBM-e kritične razine hiperkapnije i/ili hipoksije tijekom maksimalne apneje. Zbog toga su određivani plinovi u arterijskoj krvi tijekom maksimalnog voljnog zadržavanja daha. Jedanaest zdravih ispitanika zadržavalo je dah nakon što su prethodno udisali zrak, hiperoksično-normokapničnu, hipoksično-normokapničnu i normooksično-hipekapničnu mješavinu plinova. Prethodno udisanje plinskih mješavina olakšalo je nastup IBM-a, skraćujući vrijeme njihova nastupa za oko 46% (hiperoksični uvjeti), odnosno za oko 80% (hipoksični uvjeti) u usporedbi s prethodnim udisanjem zraka. Zamijećena jaka korelacija (r=0.83, p=0.002) između parcijalnog tlaka ugljičnog dioksida (PaCO2) i trenutka nastupa IBM-a, a nakon prethodnog udisanja hiperoksične i hiperkapnične plinske mješavine, govori u prilog postojanja mogućeg PaCO2 praga za nastup IBM-a, koji iznosi oko 6.5 ± 0.5 kPa. Prag za parcijalni tlak kisika u arterijskoj krvi (PaO2) pri kojem nastupa IBM nije se mogao odrediti. Međutim, zamijetili smo da je nastup IBM-a, tijekom maksimalne apneje, barem djelomice ovisan o međuodnosu PaO2 i PaCO2. Prema tome, ova studija ukazuje na složen odnos između O2 i CO2 u arterijskoj krvi i fiziološkog odgovora na maksimalno zadržavanje daha.The growing urge to breathe that occurs during breath-holding results in development of involuntary breathing movements (IBMs). The present study determined whether IBMs are initiated at critical levels of hypercapnia and/or hypoxia during maximal apnoea. Arterial blood gasses at the onset of IBM were monitored during maximal voluntary breath-holds. Eleven healthy men performed breath holds after breathing air, hyperoxic–normocapnia, hypoxic–normocapnia, and normoxic–hypercapnia. Prebreathing of the gas mixtures facilitated the IBM onset, reducing the time-to-onset for ~46% (hyperoxic condition) and for ~80% (hypoxic condition) compared to the normoxic air breathing time. A strong correlation (R = 0.83, P = 0.002) between arterial partial pressure of CO2 (PaCO2 ) at IBM onset after pre-breathing hyperoxic and hypercapnic gas mixtures was observed, suggesting the existence of a possible IBM PaCO2 threshold level of ~6.5 ± 0.5 kPa. No clear “threshold” was observed for partial pressure of arterial O2 (PaO2 ). However, we observed that IBM onset was influenced, in part, by an interaction between PaO2 and PaCO2 levels during maximal apnoea. This study demonstrated the complex interaction between arterial blood-gases and the physiological response to maximal breath holding

Chemoreceptor threshold for the onset of involuntary respiratory movements during maximal apnea

Potreba za disanjem tijekom zadržavanja daha rezultira nastankom nevoljnih dišnih pokreta. Ovom se studijom željelo utvrditi pokreću li IBM-e kritične razine hiperkapnije i/ili hipoksije tijekom maksimalne apneje. Zbog toga su određivani plinovi u arterijskoj krvi tijekom maksimalnog voljnog zadržavanja daha. Jedanaest zdravih ispitanika zadržavalo je dah nakon što su prethodno udisali zrak, hiperoksično-normokapničnu, hipoksično-normokapničnu i normooksično-hipekapničnu mješavinu plinova. Prethodno udisanje plinskih mješavina olakšalo je nastup IBM-a, skraćujući vrijeme njihova nastupa za oko 46% (hiperoksični uvjeti), odnosno za oko 80% (hipoksični uvjeti) u usporedbi s prethodnim udisanjem zraka. Zamijećena jaka korelacija (r=0.83, p=0.002) između parcijalnog tlaka ugljičnog dioksida (PaCO2) i trenutka nastupa IBM-a, a nakon prethodnog udisanja hiperoksične i hiperkapnične plinske mješavine, govori u prilog postojanja mogućeg PaCO2 praga za nastup IBM-a, koji iznosi oko 6.5 ± 0.5 kPa. Prag za parcijalni tlak kisika u arterijskoj krvi (PaO2) pri kojem nastupa IBM nije se mogao odrediti. Međutim, zamijetili smo da je nastup IBM-a, tijekom maksimalne apneje, barem djelomice ovisan o međuodnosu PaO2 i PaCO2. Prema tome, ova studija ukazuje na složen odnos između O2 i CO2 u arterijskoj krvi i fiziološkog odgovora na maksimalno zadržavanje daha.The growing urge to breathe that occurs during breath-holding results in development of involuntary breathing movements (IBMs). The present study determined whether IBMs are initiated at critical levels of hypercapnia and/or hypoxia during maximal apnoea. Arterial blood gasses at the onset of IBM were monitored during maximal voluntary breath-holds. Eleven healthy men performed breath holds after breathing air, hyperoxic–normocapnia, hypoxic–normocapnia, and normoxic–hypercapnia. Prebreathing of the gas mixtures facilitated the IBM onset, reducing the time-to-onset for ~46% (hyperoxic condition) and for ~80% (hypoxic condition) compared to the normoxic air breathing time. A strong correlation (R = 0.83, P = 0.002) between arterial partial pressure of CO2 (PaCO2 ) at IBM onset after pre-breathing hyperoxic and hypercapnic gas mixtures was observed, suggesting the existence of a possible IBM PaCO2 threshold level of ~6.5 ± 0.5 kPa. No clear “threshold” was observed for partial pressure of arterial O2 (PaO2 ). However, we observed that IBM onset was influenced, in part, by an interaction between PaO2 and PaCO2 levels during maximal apnoea. This study demonstrated the complex interaction between arterial blood-gases and the physiological response to maximal breath holding

Chemoreceptor threshold for the onset of involuntary respiratory movements during maximal apnea

Potreba za disanjem tijekom zadržavanja daha rezultira nastankom nevoljnih dišnih pokreta. Ovom se studijom željelo utvrditi pokreću li IBM-e kritične razine hiperkapnije i/ili hipoksije tijekom maksimalne apneje. Zbog toga su određivani plinovi u arterijskoj krvi tijekom maksimalnog voljnog zadržavanja daha. Jedanaest zdravih ispitanika zadržavalo je dah nakon što su prethodno udisali zrak, hiperoksično-normokapničnu, hipoksično-normokapničnu i normooksično-hipekapničnu mješavinu plinova. Prethodno udisanje plinskih mješavina olakšalo je nastup IBM-a, skraćujući vrijeme njihova nastupa za oko 46% (hiperoksični uvjeti), odnosno za oko 80% (hipoksični uvjeti) u usporedbi s prethodnim udisanjem zraka. Zamijećena jaka korelacija (r=0.83, p=0.002) između parcijalnog tlaka ugljičnog dioksida (PaCO2) i trenutka nastupa IBM-a, a nakon prethodnog udisanja hiperoksične i hiperkapnične plinske mješavine, govori u prilog postojanja mogućeg PaCO2 praga za nastup IBM-a, koji iznosi oko 6.5 ± 0.5 kPa. Prag za parcijalni tlak kisika u arterijskoj krvi (PaO2) pri kojem nastupa IBM nije se mogao odrediti. Međutim, zamijetili smo da je nastup IBM-a, tijekom maksimalne apneje, barem djelomice ovisan o međuodnosu PaO2 i PaCO2. Prema tome, ova studija ukazuje na složen odnos između O2 i CO2 u arterijskoj krvi i fiziološkog odgovora na maksimalno zadržavanje daha.The growing urge to breathe that occurs during breath-holding results in development of involuntary breathing movements (IBMs). The present study determined whether IBMs are initiated at critical levels of hypercapnia and/or hypoxia during maximal apnoea. Arterial blood gasses at the onset of IBM were monitored during maximal voluntary breath-holds. Eleven healthy men performed breath holds after breathing air, hyperoxic–normocapnia, hypoxic–normocapnia, and normoxic–hypercapnia. Prebreathing of the gas mixtures facilitated the IBM onset, reducing the time-to-onset for ~46% (hyperoxic condition) and for ~80% (hypoxic condition) compared to the normoxic air breathing time. A strong correlation (R = 0.83, P = 0.002) between arterial partial pressure of CO2 (PaCO2 ) at IBM onset after pre-breathing hyperoxic and hypercapnic gas mixtures was observed, suggesting the existence of a possible IBM PaCO2 threshold level of ~6.5 ± 0.5 kPa. No clear “threshold” was observed for partial pressure of arterial O2 (PaO2 ). However, we observed that IBM onset was influenced, in part, by an interaction between PaO2 and PaCO2 levels during maximal apnoea. This study demonstrated the complex interaction between arterial blood-gases and the physiological response to maximal breath holding

COMPARISON OF THE LEVEL OF KNOWLEDGE ON CARDIOPULMONARY RESUSCITATION AMONG STUDENTS OF THE MEDICALSCHOOL SPLIT AND NURSING STUDENTS OF THE UNIVERSITY DEPARTMENT OF HEALTH STUDIES IN SPLIT

Cilj: Usporediti znanja učenika Zdravstvene škole Split i studenata Sveučilišnog odjela zdravstvenih studija u Splitu o kardiopulmonalnoj reanimaciji. Metode: U ovom istraživanju sudjelovalo je 186 ispitanika, 94 studenta i 92 učenika. Korišten je mjerni instrument upitnik CAEPCR. Čimbenici uključenja ispitanika bili su dob >18 godina, bez dodatnih čimbenika isključenja. Rezultati: Zbrajanjem ispravnih odgovora u pitanjima znanja, dokazali smo statističku značajnu razliku prema ukupnom zbroju ispravnih odgovora na pitanja znanja između učenika i studenata (Z=2,96; r=0,217; P=0,003). Medijan ukupnog zbroja točnih odgovora u učenika Zdravstvene škole Split iznosi 6, a u studenata na Sveučilišnom odjelu zdravstvenih studija u Splitu iznosi 5. Postoji statistički značajna, slaba negativna korelacija ukupnog zbroja pozitivnih odgovora sa životnom dobi ispitanika (ρ=-0,195; P=0,008). Raspodjela ukupnog zbroja ispravnih odgovora na pitanja znanja prema 5 formiranih skupina statistički se značajno razlikovala između ustanova. Zaključak: S obzirom na dobivene rezultate možemo zaključiti da je razina znanja veća kod ispitanika Zdravstvene srednje škole u odnosu na studente Sveučilišnog odjela zdravstvenih studija u Splitu. Tom rezultatu doprinosi razlika u provedenoj edukaciji prikazana u nastavnim planovima i programima. Zbog razlike u edukaciji odnosno u trajanju edukacije i vremena protijeka od edukacije, potrebno je provesti daljnje detaljnije istraživanje o utjecaju tih čimbenika na znanje.Aim: To examine the knowledge of the students of the Health school Split and the students of the University Department of health studies in Split in cardiopulmonary resuscitation. Methods: This study included186 examinees, 94 university students and 92 health school students. A measuring instrument for this study was a CAEPCR questionnaire. Inclusion criteria were age >18 years. There were no additional exclusion criteria. Results: We proved a statistically significant difference in the total number of correct answers to the knowledge questions between the University students and High School students (Z=2.96; r=0.217; P=0.003). The median total sum of correct answers of students in Medical school Split is 6, and in students from the University Department of Health Studies in Split is 5. There is statistical significance, a weak negative correlation of the total number of positive responses with the age of the subjects (ρ=-0.195; P=0.008). The distribution of the total sums of correct answers according to the 5 statistical groups formed is generally differed between institutions. Conclusion: Considering the obtained results, we have concluded that the level of knowledge is higher in the students of the Health school, unlike the students of the University Department of Health studies in Split. This result was intensified by the differen-ce in education shown in the curricula. Due to the difference in education, in the duration of education and the time elapsed since education, further research on the impact of these factors on knowledge is neede

Anesteziologija i intenzivna medicina za studente medicine, dentalne medicine i zdravstvene studije

Sveučilišni udžbenik iz anesteziologije i intezivne medicin

The Effects of Involuntary Respiratory Contractions on Cerebral Blood Flow during Maximal Apnoea in Trained Divers.

The effects of involuntary respiratory contractions on the cerebral blood flow response to maximal apnoea is presently unclear. We hypothesised that while respiratory contractions may augment left ventricular stroke volume, cardiac output and ultimately cerebral blood flow during the struggle phase, these contractions would simultaneously cause marked 'respiratory' variability in blood flow to the brain. Respiratory, cardiovascular and cerebrovascular parameters were measured in ten trained, male apnoea divers during maximal 'dry' breath holding. Intrathoracic pressure was estimated via oesophageal pressure. Left ventricular stroke volume, cardiac output and mean arterial pressure were monitored using finger photoplethysmography, and cerebral blood flow velocity was obtained using transcranial ultrasound. The increasingly negative inspiratory intrathoracic pressure swings of the struggle phase significantly influenced the rise in left ventricular stroke volume (R (2) = 0.63, P<0.05), thereby contributing to the increase in cerebral blood flow velocity throughout this phase of apnoea. However, these contractions also caused marked respiratory variability in left ventricular stroke volume, cardiac output, mean arterial pressure and cerebral blood flow velocity during the struggle phase (R (2) = 0.99, P<0.05). Interestingly, the magnitude of respiratory variability in cerebral blood flow velocity was inversely correlated with struggle phase duration (R (2) = 0.71, P<0.05). This study confirms the hypothesis that, on the one hand, involuntary respiratory contractions facilitate cerebral haemodynamics during the struggle phase while, on the other, these contractions produce marked respiratory variability in blood flow to the brain. In addition, our findings indicate that such variability in cerebral blood flow negatively impacts on struggle phase duration, and thus impairs breath holding performance