Clamping Group Research Articles

Selective clamping during robot-assisted partial nephrectomy in patients with a solitary kidney: is it safe and does it help?

To obtain the most accurate assessment of the risks and benefits of selective clamping in robot-assisted partial nephrectomy (RAPN) we evaluated outcomes of this technique vs those of full clamping in patients with a solitary kidney undergoing RAPN. Data from institutional review board-approved retrospective and prospective databases from 2006 to 2019 at multiple institutions with sharing agreements were evaluated. Patients with a solitary kidney were identified and stratified based on whether selective or full renal artery clamping was performed. Both groups were analysed with regard to demographics, risk factors, intra-operative complications, and postoperative outcomes using chi-squared tests, Fisher's exact tests, t-tests and Mann-Whitney U-tests. Our initial cohort consisted of 4112 patients, of whom 72 had undergone RAPN in a solitary kidney (51 with full clamping and 21 with selective clamping). There were no significant differences in demographics, tumour size, baseline estimated glomerular filtration rate (eGFR), or warm ischaemia time (WIT) between the groups (Table 1). Intra-operative outcomes, including estimated blood loss, operating time, and intra-operative complications were similar in the two groups. Short- and long-term postoperative percentage change in eGFR, frequency of acute kidney injury (AKI), and frequency of de novo chronic kidney disease (CKD) were also not significantly different between the two techniques. In a large cohort of patients with solitary kidney undergoing RAPN, selective clamping resulted in similar intra-operative and postoperative outcomes compared to full clamping and conferred no additional risk of harm. However, selective clamping did not appear to provide any functional advantage over full clamping as there was no difference observed in the frequency of AKI, CKD or change in eGFR. Short WIT in both groups (<15min) may have prevented identification of benefits in the selective clamping group; a similar study analysing cases with longer WIT may elucidate any beneficial effects of selective clamping.

Acute Kidney Injury Following Elective Open Aortic Repair with Suprarenal Clamping.

Objective: To investigate predictors of acute kidney injury (AKI) following open aortic repair (OAR) requiring suprarenal clamping.Methods: The study included 833 nonhemodialysis patients who had undergone elective OAR (with suprarenal clamping, n=73; with infrarenal clamping, n=760). We evaluated AKI as defined by the criteria of the Kidney Disease Improving Global Outcomes (KDIGO) and compared in-hospital outcomes between the two groups. We also investigated the effects of AKI on outcomes, factors related to post-suprarenal clamping AKI, and efficacy of hypothermic renal perfusion (HRP) in the suprarenal clamping group.Results: For the suprarenal vs. infrarenal clamping group, in-hospital mortality was 0% (0/73) vs. 0.5% (4/760). The incidence of AKI was greater in the suprarenal clamping group (37% vs. 15%, P<0.001), and the hospital stay for patients with AKI was longer than for those patients without AKI (median, 21 days vs. 16 days; P=0.005). Renal ischemia time and bleeding volume >1,000 mL were associated with post-suprarenal clamping AKI. Renal ischemia time was longer with HRP (n=15) than without HRP (n=58) (median, 51 min vs. 33 min; P=0.011), and HRP did not decrease the incidence of AKI (40% vs. 36%; P=0.78).Conclusion: Prolonged renal ischemia and substantial intraoperative bleeding are associated with postoperative AKI following suprarenal clamping.

Surgical Repair of Juxtarenal Abdominal Aortic Aneurysms and safety of Suprarenal Aortic Clamping.

Juxtarenal abdominal aortic aneurysm (AAA) comprises 15-20% of all AAAs and often requires open surgical repair (OSR) due to anatomical limitations associated with endovascular aneurysm repair (EVAR), particularly in the case of hostile proximal necks. This study aimed to evaluate short- and long-term outcomes of suprarenal clamping during OSR of juxtarenal AAAs and compare the outcomes of this technique with those of infrarenal clamping for AAAs. Between January 1 2014, and December 31 2016, 289 consecutive patients aged ≥40years underwent primary repair for infrarenal AAAs, including 141 OSRs and 148 EVARs. Of the 141 patients, 20 were excluded and totally, 121 patients were included. All patients had fusiform-type AAAs and were divided into infrarenal (N=98) or suprarenal (N=23) clamp groups. The mean follow-up period was 51.4months (95% CI: 48.6-54.2). Mean survival time was 51.4months (95% CI: 48.6-54.2). Thirty-day mortality was 0.8%, and there was no significant difference between two groups (P>.999). Renal complication in infrarenal clamp group was 4.1% and suprarenal clamp group was 4.3% (P>.999). Old age (HR: 1.084; 95% CI: 1.025-1.147; P=.005) and high ASA score (HR: 2.361; 95% CI: 1.225-4.553; P=.010) were substantially associated with in-hospital complications. Although endovascular procedures for repairing juxtarenal AAAs, such as fenestrated EVAR, have been developed, surgical repair is the standard treatment for juxtarenal AAAs. Morbidity and mortality due to open surgery were not higher in the juxtarenal AAA group than in the infrarenal AAA group. Therefore, need for suprarenal clamp should not preclude OSR and also there is continued need for training in surgical exposure of juxtarenal AAA and OSR.

The effect of bilateral uterine artery ligation versus intermittent clamping of uterine and ovarian artery on blood loss during abdominal myomectomy : A randomized controlled trial

Background: Myomectomies are more commonly performed than hysterectomies, mainly due to the fact that patients desire to retain their uterus for psychological, reproductive and cultural reasons even after completing their families. The average volume of blood loss during abdominal myomectomy is 200 to 800 mL. Surgical hemorrhage may result in anemia, hypovolemia, and coagulation abnormalities.Aim: To compare between bilateral uterine artery ligation and intermittent clamping of uterine and ovarian artery on amount of blood loss during abdominal myomectomy.Patients and Methods: This study was conducted at Ain-Shams University Maternity Hospital on 90 women with symptomatic myomas in the postmenstrual period presented by abnormal uterine bleeding, dull aching lower abdominal pain, dyspareunia, pressure symptoms, progressive abdominal enlargement or pelvic heaviness, diagnosed based on clinical examination and ultrasound scan with pre-operative hemoglobin level above 10gm/dl.Results: The preoperative Hb was 11.6 gm % and 11.8gm% for both clamping and ligation one respectively, and post-operative Hb for the groups was 9.4 gm% and 9.2 gm% for the 2 groups respectively. There was no significant difference between both groups regarding postoperative drop of hemoglobin which was 0.8 gm % in the clamping group and 1.1 gm% in the ligation group. Estimated inraoperative blood loss start was significantly fewer among clamping group than among ligation group. Hemoglobin reduction was significantly fewer among clamping group than among ligation group.Conclusion: Based on the results obtained by this study, intermittent clamping of uterine and ovarian artery is a preferred approach than bilateral uterine artery ligation on blood loss during abdominal myomectomy.

Delayed cord clamping in Rh-alloimmunised infants: a randomised controlled trial.

Despite advancement in medical care, Rh alloimmunisation remains a major cause of neonatal hyperbilirubinaemia, neuro-morbidity, and late-onset anaemia. Delayed cord clamping (DCC), a standard care now-a-days, is yet not performed in Rh-alloimmunised infants due to paucity of evidence. Hence, we randomised these infants of 28- to 41-week gestation to delayed cord clamping (N = 36) or early cord clamping (N = 34) groups. The primary outcome variable was venous packed cell volume (PCV) at 2h of birth. The secondary outcomes were incidence of double volume exchange transfusion (DVET) and partial exchange transfusion (PET), duration of phototherapy (PT), functional echocardiography (parameters measured: superior vena cava flow, M-mode fractional shortening, left ventricular output, myocardial perfusion index, and inferior vena cava collapsibility) during hospital stay, and blood transfusion (BT) until 14weeks of life. Neonates were managed as per unit protocol. The baseline characteristics of enrolled infants were comparable between the groups. The median (IQR) gestation and mean (SD) birth weight of enrolled infants were 35 (33-37) weeks and 2440 (542) g, respectively. The DCC group had a higher mean PCV at 2h of life (48.4 ± 9.2 vs. 43.5 ± 8.7, mean difference 4.9% (95% CI 0.6-9.1), p = 0.03). However, incidence of DVET and PET, duration of PT, echocardiography parameters, and BT until 14weeks of postnatal age were similar between the groups.Conclusion: DCC in Rh-alloimmunised infants improved PCV at 2h of age without significant adverse effects.Trial registration: Clinical Trial Registry of India (CTRI), Ref/2016/11/012572 http://ctri.nic.in/Clinicaltrials, date of trial registration 19.12.2016, date of first patient enrolment 1 January 2017.What is Known:•Delayed cord clamping improves haematocrit, results in better haemodynamic stability, and decreases the need of transfusion in early infancy.•However,due to lack of evidence,potential risk of hyperbilirubinaemia, andexacerbation of anaemia(following delayed cord clamping), early cord clamping is the usual norm in Rh-alloimmunised infantsinfants.What is New:•Delayed cord clamping in Rh-alloimmunised infants improves haematocrit at 2h of life without any increase in incidence of serious adverse effects.

Timing of umbilical cord clamping and neonatal jaundice in singleton term pregnancy

BackgroundDelayed cord clamping was not adopted widely in China because of the potential effect of neonatal hyperbilirubinemia, jaundice and polycythemia, and the optimal cord clamping time remained controversial. AIMTo assess the effect of delayed cord clamping versus early cord clamping on neonatal jaundice for term infants. Study designThis retrospective study included 1981 mother-infant pairs, who were assigned to early cord clamping groups (n = 1005) and delayed cord clamping group (n = 949). The delayed cord clamping included three subgroups (30–60 s, 61–90 s, 91–120 s). The main outcomes were transcutaneous bilirubin levels at 0 to 4 days of age, the rate of jaundice requiring phototherapy, the neonatal hematological status at 1 to 3 days after birth. ResultsCompared with the early cord clamping group, the neonatal transcutaneous bilirubin level did not differ and the neonatal hematological status (hemoglobin and hematocrit levels) were improved in combined and three subgroups of delayed cord clamping group. Increasing the duration of cord clamping from 90 s to 120 s did not result in further increases in hemoglobin and hematocrit levels but led to a trend towards a higher risk of neonatal jaundice requiring phototherapy and neonatal polycythemia. ConclusionsDelayed cord clamping for <90 s in healthy term infants may not only improve the early hematological status of newborns but also avoid excessive neonatal jaundice requiring phototherapy.

Effects of clamping umbilical cord on the neonatal viability of puppies delivered by cesarean section.

In human neonates, when the umbilical cord is kept intact postpartum, blood continues to flow to the neonate, but this procedure might be difficult in dogs owing to a shorter umbilical cord and several neonates in a litter. However, it might be possible to detach the placenta and keep the umbilical cord intact, allowing residual blood to flow to the puppies. This study compared the effects of clamping versus no clamping of the umbilical cord in dogs born by cesarean section on neonatal vitality. The puppies were assessed by Apgar and reflex scores. Fifty puppies delivered from 16 bitches were randomly allocated to receive immediate umbilical cord clamping (n=25) or no clamping for at least 3 min after the onset of breathing (n=25). The puppies were assessed during the first 5 min of life and 10 min after the first assessment. The no clamping group showed significantly higher Apgar scores (second assessment, P<0.01) and reflex scores (first and second assessments, P<0.05) than the clamping group, implying higher vitality in the no clamping group. The differences observed between the moments (first versus second assessment) of each group was significant (P<0.01), revealing higher vitality in the second assessment. The results suggest that keeping the umbilical cord intact for at least 3 min after the onset of breathing may contribute to increased vitality in puppies delivered by cesarean section without any negative consequences.

Protective Effects of Cold Ringer's Solution Perfusion in Abdominal Aortic Surgery Requiring Renal Artery Clamp

Treating abdominal aortic aneurysms (AAA) of the juxtarenal artery with renal artery clamps burdens the kidneys. We investigated the outcomes of intra-operative renal artery perfusion using the cold Ringer's solution method for renal protection. We enrolled 290 AAA patients who underwent open aortic repair. Surgical outcomes were investigated based on renal protection. We evaluated 231 patients requiring infrarenal artery clamp (Group I), and 59 patients requiring perfusion in addition to the clamp (Group J). Patient demographics, acute kidney injury (AKI) incidence (Group I: 11.7% and Group J: 20.3%), hospital mortality (Group I: 1.3% and Group J: 1.7%), and 30-day mortality (Group I: 0.4% and Group J: 0%) were not different between the groups. The AKI incidence was low (13%) in cases requiring a renal artery clamp for ≥45 min (n=40). Perfusion with cold Ringer's solution offers renal protection and may improve surgical outcomes.

VAGINAL HYSTERECTOMYUSING VESSEL SEALING CLAMP VERSUS CONVENTIONAL SURGERY; A RANDOMISED TRIAL

Objective: To compare the effects of electrical bipolar vessel sealing clamp and conventional suturing on postoperative pain, operative time, blood loss, and costs, in women undergoing vaginal hysterec- tomy. Patients and Methods: 20 women scheduled to undergo vaginal hysterectomy for prolapsed and non prolapsed uterus with benign indication of hysterectomy. Women were randomizedrandomly into two groups;Conventional vaginal surgery Groupand a Group using vessel sealing Erbe machine.Ten patient in each group. Operative time, intraoperative assessment of blood loss, postoperative pain, and estimated cost were evaluated and compared between both groups. Results: Pain was evaluated few hours post-operative.Patients in the vessel-sealing clamp group showed statisticallysignificant less pain (5.7 versus 4.5 on a scale of 0–10, P= 0.03), but this followed by comparable pain in both groups later. Operative time wasshorter in vessel sealing clamp group (39 versus 61 minutes = P< 0.05). Amount of Blood lostwas also less vessel sealing clamp group.How- ever, regarding the estimated coast, no significant difference between both groups (2903 versus 3102, P=0.26). Conclusion: Using electrical bipolar vessel sealing clamp during vag- inal hysterectomy showed less pain on the first few hours after surgery but not in the following days, shorter operative time, less operative blood loss, with no statistically significant differences in costwere found between the two groups. (Pictures and videos available).

Nephron sparing surgery for renal tumors-comparison of off-clamp partial nephrectomy with hilar clamping.

Background and Objective:Open partial nephrectomy (PN) is still considered gold standard procedure for T1 localized renal tumors. Conventional technique involves clamping of the renal artery with or without vein however, renal ischemia produces a certain level of damage to the kidneys. This study aims to investigate potential effect of off-clamp vs. hilar clamping PN on renal function.Methods:This is a retrospective cohort study of patients who underwent unilateral, open partial nephrectomy for renal tumors b/w January 2009 December 2016 at our institution. A total of 90 partial nephrectomies were performed of which 65 cases were eligible for analysis. Non clamping technique was used in 43 while clamp was applied in 22 patients. Variables studied were patients’ demographics, clinical variables, the laterality, tumors size and location, R.E.N.A.L nephrometry score, blood loss, tumor histology and surgical margins. Patients’ renal function (serum creatinine and eGFR) were determined pre-operatively, at 3 and 12 months follow up. Data was analyzed on SPSS v. 22.Results:Both the groups were comparable with regards to pre-operative renal function. Mean radiological size of tumor was 4.71±1.31 and 3.81±1.0 (0.003) in two groups respectively. Mean R.E.N.A.L nephrometry score was 6.1±1.5 in off-clamp group compared to 7.05 ± 1.7 in clamp group (p=0.04). No statistically significant difference was found in operative duration, blood loss, positive surgical margins and intra/ peri-operative complications. At three months and one year, renal function was better preserved in non-clamp group compared to clamp group (p=0.001 and 0.007 respectively).Conclusion:Off clamp open partial nephrectomy is safe and feasible option leading to less decline in renal function.

A Prospective observational study of single-dose prophylactic antibiotic in caesarean delivery and its effect on maternal infectious morbidity

Introduction: Caserean delivery is the most commonly performed in obstetrics. Antibiotics have revolutionised the surgical practice in this era. But multidrug resistance is a challenging issue in practice. So antibiotics have to be administered judiciously at the appropriate time with respect to surgery. Aim: To determine whether the administration of single-dose injection ceftriaxone 1gm intravenously prior to skin incision was superior to the administration at the time of cord clamping for prevention of post-caesarean maternal infectious. Material and Methods: A prospective observational study was conducted in BLDE (DU) Shri B M Patil medical college and research centre, Vijayapura, Karnataka. Patients undergoing caesarean sections for singleton term pregnancies both elective and emergency with intact membranes were included in the study during the one-year period. Alternatively, Group A received 1gm Injection ceftriaxone intravenously 60 mins before skin incision and group B received at the time of cord clamping during surgery. Results: Incidence of obstetric complications such as nausea (0.5% vs 0.0%) and wound infections (6.6% vs 4.1%) were more in patients received a single dose of ceftriaxone at cord clamping than patients received the same antibiotic, preoperatively. Whereas, the incidence of postoperative fever was more in patients received a single dose of ceftriaxone preoperatively (4.1%) than intraoperatively (3.3%) which was although not significant but is an important finding in our study. Conclusion: Administration of single-dose antibiotic either preoperatively or at the time of cord clamping was not statistically significant in reducing the incidence of wound infections. However, we noticed that the antibiotic administration pre-operatively reduced the infections compared to the cord clamp group.

The “DUC” trial: a pilot randomized controlled trial of immediate versus delayed cord clamping in preterm infants born between 24 and 32 weeks gestation

Purpose To determine the feasibility of a randomized controlled trial of delayed umbilical cord clamping in preterm infants. Methods Following informed consent, women between 24 to 32 weeks gestation experiencing imminent preterm birth were randomly assigned to either an immediate cord clamping (ICC) or delayed cord clamping (DCC) group. Umbilical cord clamping directions were 0–15 s for the ICC group and 30–45 s for the DCC group. Information regarding recruitment rate and trial compliance was collected. Neonatal outcomes of intraventricular hemorrhage (IVH), sepsis, anemia, and hyperbilirubinemia were also compared between the two groups. This trial was registered at https://clinicaltrials.gov/. (ClinicalTrials.gov Identifier: NCT00562536). Results Thirty-eight women were recruited in total, 19 each to the ICC and DCC groups respectively. The study recruitment rate was 33% and study compliance rate was 97%. The average time for cord clamping was 5.4 s in the ICC group and 39.7 s in the DCC group (p < .05). The incidence of IVH and sepsis was the same in both groups (16 and 11% respectively). Thirty-seven percent of the ICC group and 21% of the DCC group required a blood transfusion. Hyperbilirubinemia requiring phototherapy occurred in 37% of the ICC group and 26% of the DCC group. Conclusion This study demonstrates that a trial of a short delay in umbilical cord clamping (30–45 s) is feasible for women and physicians. Larger scale studies of long term outcomes are warranted.

Effect of delayed cord clamping on cerebral tissue oxygen saturation in newborns

Objective To investigate the influence of different delayed cord clamping(DCC) time on cerebral tissue oxygen saturation in normal newborns after birth and to explore the causes. Methods From November 2018 to February 2019, 164 healthy full term newborns were delivered in the Department of Obstetrics, Binhu Hospital, the Southern District of the Third Affiliated Hospital of Anhui Medical University.The newborns were divided into early cord clamping (ECC) group, DCC groups for 1 minute, 2 minutes and 3 minutes according to the different cord clamping time, and the changes of cerebral tissue oxygen saturation index (cTOI) and cerebral tissue hemoglobin index(cTHI) were monitored by near infrared spectroscopy (NIRS) for 15 minutes after birth. Results After birth, cTOI increased gradually but cTHI was basically stable.The cTOI in DCC group was higher than ECC group, but there was no difference between group 3 and group 4.In ECC group, the cTOI tended to be stable about 6 minutes after birth, and the stable range was 55%-59%.In DCC group, group 2 tended to be stable about 8 minutes after birth, and the stable range was 59%-64%.Group 3 and group 4 tended to be stable about 10 minutes after birth, the stable range was 64%-69%.There was no difference in cTHI among the groups. Conclusions Delayed cord clamping can increase cerebral oxygenation in newborns.The cause may not be due to the direct increase in cerebral blood flow, but the increase in brain oxygen content, and the optimal duration of DCC is 2 minutes. Key words: Delayed cord clamping; Cerebral tissue oxygen saturation; Cerebral tissue hemoglobin; Near infrared spectroscopy; Infant, newborn

Effect of Delayed vs Immediate Umbilical Cord Clamping on Maternal Blood Loss in Term Cesarean Delivery

The American College of Obstetricians and Gynecologists recommends a delay in umbilical cord clamping in term neonates for at least 30 to 60 seconds after birth. Most literature supporting this practice is from low-risk vaginal deliveries. There are no published data specific to cesarean delivery. To compare maternal blood loss with immediate cord clamping vs delayed cord clamping in scheduled cesarean deliveries at term (≥37 weeks). Randomized clinical trial performed at 2 hospitals within a tertiary academic medical center in New York City from October 2017 to February 2018 (follow-up completed March 15, 2018). A total of 113 women undergoing scheduled cesarean delivery of term singleton gestations were included. In the immediate cord clamping group (n = 56), cord clamping was within 15 seconds after birth. In the delayed cord clamping group (n = 57), cord clamping was at 60 seconds after birth. The primary outcome was change in maternal hemoglobin level from preoperative to postoperative day 1, which was used as a proxy for maternal blood loss. Secondary outcomes included neonatal hemoglobin level at 24 to 72 hours of life. All of the 113 women who were randomized (mean [SD] age, 32.6 [5.2] years) completed the trial. The mean preoperative hemoglobin level was 12.0 g/dL in the delayed and 11.6 g/dL in the immediate cord clamping group. The mean postoperative day 1 hemoglobin level was 10.1 g/dL in the delayed group and 9.8 g/dL in the immediate group. There was no significant difference in the primary outcome, with a mean hemoglobin change of -1.90 g/dL (95% CI, -2.14 to -1.66) and -1.78 g/dL (95% CI, -2.03 to -1.54) in the delayed and immediate cord clamping groups, respectively (mean difference, 0.12 g/dL [95% CI, -0.22 to 0.46]; P = .49). Of 19 prespecified secondary outcomes analyzed, 15 showed no significant difference. The mean neonatal hemoglobin level, available for 90 neonates (79.6%), was significantly higher with delayed (18.1 g/dL [95% CI, 17.4 to 18.8]) compared with immediate (16.4 g/dL [95% CI, 15.9 to 17.0]) cord clamping (mean difference, 1.67 g/dL [95% CI, 0.75 to 2.59]; P < .001). There was 1 unplanned hysterectomy in each group. Among women undergoing scheduled cesarean delivery of term singleton pregnancies, delayed umbilical cord clamping, compared with immediate cord clamping, resulted in no significant difference in the change in maternal hemoglobin level at postoperative day 1. ClinicalTrials.gov Identifier: NCT03150641.

Association of Umbilical Cord Milking vs Delayed Umbilical Cord Clamping With Death or Severe Intraventricular Hemorrhage Among Preterm Infants

Umbilical cord milking as an alternative to delayed umbilical cord clamping may provide equivalent benefits to preterm infants, but without delaying resuscitation. To determine whether the rates of death or severe intraventricular hemorrhage differ among preterm infants receiving placental transfusion with umbilical cord milking vs delayed umbilical cord clamping. Noninferiority randomized clinical trial of preterm infants (born at 23-31 weeks' gestation) from 9 university and private medical centers in 4 countries were recruited and enrolled between June 2017 and September 2018. Planned enrollment was 750 per group. However, a safety signal comprising an imbalance in the number of severe intraventricular hemorrhage events by study group was observed at the first interim analysis; enrollment was stopped based on recommendations from the data and safety monitoring board. The planned noninferiority analysis could not be conducted and a post hoc comparison was performed instead. Final date of follow-up was December 2018. Participants were randomized to umbilical cord milking (n = 236) or delayed umbilical cord clamping (n = 238). The primary outcome was a composite of death or severe intraventricular hemorrhage to determine noninferiority of umbilical cord milking with a 1% noninferiority margin. Among 540 infants randomized, 474 (88%) were enrolled and completed the trial (mean gestational age of 28 weeks; 46% female). Twelve percent (29/236) of the umbilical cord milking group died or developed severe intraventricular hemorrhage compared with 8% (20/238) of the delayed umbilical cord clamping group (risk difference, 4% [95% CI, -2% to 9%]; P = .16). Although there was no statistically significant difference in death, severe intraventricular hemorrhage was statistically significantly higher in the umbilical cord milking group than in the delayed umbilical cord clamping group (8% [20/236] vs 3% [8/238], respectively; risk difference, 5% [95% CI, 1% to 9%]; P = .02). The test for interaction between gestational age strata and treatment group was significant for severe intraventricular hemorrhage only (P = .003); among infants born at 23 to 27 weeks' gestation, severe intraventricular hemorrhage was statistically significantly higher with umbilical cord milking than with delayed umbilical cord clamping (22% [20/93] vs 6% [5/89], respectively; risk difference, 16% [95% CI, 6% to 26%]; P = .002). In this post hoc analysis of a prematurely terminated randomized clinical trial of umbilical cord milking vs delayed umbilical cord clamping among preterm infants born at less than 32 weeks' gestation, there was no statistically significant difference in the rate of a composite outcome of death or severe intraventricular hemorrhage, but there was a statistically significantly higher rate of severe intraventricular hemorrhage in the umbilical cord milking group. The early study termination and resulting post hoc nature of the analyses preclude definitive conclusions. ClinicalTrials.gov Identifier: NCT03019367.

Intact cord resuscitation versus early cord clamping in the treatment of depressed newborn infants during the first 10\u2009minutes of birth (Nepcord III) \u2013 a randomized clinical trial

BackgroundExperiments have shown improved cardiovascular stability in lambs if umbilical cord clamping is postponed until positive pressure ventilation is started. Studies on intact cord resuscitation on human term infants are sparse. The purpose of this study was to evaluate differences in clinical outcomes in non-breathing infants between groups, one where resuscitation is initiated with an intact umbilical cord (intervention group) and one group where cord clamping occurred prior to resuscitation (control group).MethodsRandomized controlled trial, inclusion period April to August 2016 performed at a tertiary hospital in Kathmandu, Nepal. Late preterm and term infants born vaginally, non-breathing and in need of resuscitation according to the ‘Helping Babies Breathe’ algorithm were randomized to intact cord resuscitation or early cord clamping before resuscitation. Main outcome measures were saturation by pulse oximetry (SpO2), heart rate and Apgar at 1, 5 and 10 minutes after birth.ResultsAt 10 minutes after birth, SpO2 (SD) was significantly higher in the intact cord group compared to the early cord clamping group, 90.4 (8.1) vs 85.4 (2.7) %, P < .001). In the intact cord group, 57 (44%) had SpO2 < 90% after 10 minutes, compared to 93 (100%) in the early cord clamping group, P < 0.001. SpO2 was also significantly higher in the intervention (intact cord) group at one and five minutes after birth. Heart rate was lower in the intervention (intact cord) group at one and five minutes and slightly higher at ten minutes, all significant findings. Apgar score was significantly higher at one, five and ten minutes. At 5 minutes, 23 (17%) had Apgar score < 7 in the intervention (intact cord) group compared to 26 (27%) in the early cord clamping group, P < .07. Newborn infants in the intervention (intact cord) group started to breathe and establish regular breathing earlier than in the early cord clamping group.ConclusionsThis study provides new and important information on the effects of resuscitation with an intact umbilical cord. The findings of improved SpO2 and higher Apgar score, and the absence of negative consequences encourages further studies with longer follow-up.Trial registrationClinicaltrials.gov NCT02727517, 2016/4/4

Clamping versus nonclamping thoracoscopic box ablation in long-standing persistent atrial fibrillation

ObjectiveTo compare clinical outcomes of clamping devices and linear nonclamping devices for isolation of the posterior left atrium (box) in thoracoscopic ablation of long-standing persistent atrial fibrillation. MethodsEighty patients who underwent thoracoscopic pulmonary vein and box isolation using a bipolar clamping device (42 patients) or bipolar nonclamping device (38 patients) to create the roof/inferior lesions for box isolation were included from 2 centers. Follow-up consisted of 24-hour Holter at regular intervals. Freedom from AF during 1-year follow-up and catheter repeat interventions were compared between groups. ResultsAcute intraoperative electrical isolation of the box compartment was significantly higher in the clamping group than in the nonclamping group (100% and 79%, respectively, P < .01). At 1-year follow-up, 91% of the clamping group and 79% of the nonclamping group were in sinus rhythm. During 1-year follow-up, recurrence rates did not significantly differ between the 2 groups (P = .08). Repeat catheter interventions were required in 10% of the clamping group and 21% of the nonclamping group (P = .15). Conduction gaps in the roof or inferior lesions were found in 1 patient (2%) in the clamping group versus 4 patients (11%) in the nonclamping group (P = .13). ConclusionsThoracoscopic pulmonary vein and box isolation are highly effective in restoring sinus rhythm in long-standing persistent atrial fibrillation on short-term follow-up. Comparison of clamping and nonclamping devices revealed lower rates of intraoperative exit block of the box in the nonclamping group. However, this did not translate into a significant difference in atrial fibrillation freedom at short-term (1-year) follow-up.

Alterations in Retinal Oxygen Delivery, Metabolism, and Extraction Fraction During Bilateral Common Carotid Artery Occlusion in Rats.

PurposeThe purpose of the current study was to investigate alterations in retinal oxygen delivery, metabolism, and extraction fraction and elucidate their relationships in an experimental model of retinal ischemia.MethodsWe subjected 14 rats to permanent bilateral common carotid artery occlusion using clamp or suture ligation, or they underwent sham procedure. Within 30 minutes of the procedure, phosphorescence lifetime imaging was performed to measure retinal vascular oxygen tension and derive arterial and venous oxygen contents, and arteriovenous oxygen content difference. Fluorescent microsphere and red-free retinal imaging were performed to measure total retinal blood flow. Retinal oxygen delivery rate (DO2), oxygen metabolism rate (MO2), and oxygen extraction fraction (OEF) were calculated.ResultsDO2 and MO2 were lower in ligation and clamp groups compared to the sham group, and also lower in the ligation group compared to the clamp group (P ≤ 0.05). OEF was higher in the ligation group compared to clamp and sham groups (P ≤ 0.03). The relationships of MO2 and OEF with DO2 were mathematically modeled by exponential functions. With moderate DO2 reductions, OEF increased while MO2 minimally decreased. Under severe DO2 reductions, OEF reached a maximum value and subsequently MO2 decreased with DO2.ConclusionsThe findings improve knowledge of mechanisms that can maintain MO2 and may clarify the pathophysiology of retinal ischemic injury.

Impacts of arterial ischemia or venous occlusion on vascularized groin lymph nodes in a rat model.

Reported ischemia time of vascularized lymph nodes was 5 hours. This study investigated the effects of arterial ischemia and venous occlusion on vascularized lymph node function in rats. Bilateral pedicled groin lymph node flaps were raised in 27 Lewis rats. Femoral artery and vein were separated and clamped for 1, 3, 4, or 5 hour(s). Lymph node flap perfusion and drainage were assessed by laser Doppler flowmetry and indocyanine green lymphography. Histologic changes were assessed using hematoxylin and eosin stain, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL), and glutathione assays. Perfusion units of 2.84 ± 1.41, 2.46 ± 0.64, 2.42 ± 0.37, and 2.01 ± 0.90 were measured in arterial ischemia groups, and 1.71 ± 0.45, 2.20 ± 0.98, 1.49 ± 0.35, and 0.81 ± 0.20 in venous occlusion groups after 1, 3, 4, and 5 hours of clamping, respectively. Lymphatic drainage showed mean latency periods of 5.33 ± 0.88, 9.00 ± 3.21, 10.00 ± 2.08, and 24.50 ± 11.50 seconds in arterial clamping groups, and 25.00 ± 3.61, 26.00 ± 3.06, 23.33 ± 4.41, and 152.00 ± 0 seconds in venous clamping groups, respectively. Severe medullary and cortical congestion and hemorrhage on histology and cell damage by glutathione levels and TUNEL assay were found after 4 hours of venous clamping. Arterial ischemia and venous occlusion impact the function and viability of vascularized lymph node flaps differently. The critical venous occlusion time was 4 hours.

Effect of early versus delayed cord clamping in neonate on heart rate, breathing and oxygen saturation during first 10 minutes of birth - randomized clinical trial

BackgroundDelayed cord clamping (DCC) after 180 s reduces iron deficiency up to 8 months of infancy compared to babies who received Early Cord Clamping (ECC) at less than 60 s. Experimentally DCC has shown to improve cardio-vascular stability. To evaluate the effect of delayed (≥180 s) group versus early (≤60 s) cord clamping group on peripheral blood oxygenation and heart rate up to 10 min after birth on term and late preterm infants.MethodsWe conducted a single centred randomized clinical trial in a low risk delivery unit in tertiary Hospital, Nepal. One thousand five hundred ten women, low risk vaginal delivery with foetal heart rate (FHR) ≥ 100 ≤ 160 beats per minute (bpm) and gestational age (≥33 weeks) were enrolled in the study. Participants were randomly assigned to cord clamped ≤60 s of birth and ≥ 180 s. The main outcome measures were oxygen saturation, heart rate from birth to 10 min and time of spontaneous breathing. The oxygen saturation and heart rate, the time of first breath and establishment of regular breathing was analysed using Student t-test to compare groups. We analysed the range of heart rate distributed by different centiles from the time of birth at 30 s intervals until 10 min.ResultsThe oxygen saturation was 18% higher at 1 min, 13% higher at 5 min and 10% higher at 10 min in babies who had cord clamping in delayed group compared to early group (p < 0.001). The heart rate was 9 beats lower at 1 min and3 beats lower at 5 min in delayed group compared to early group (p < 0.001). Time of first breath and regular breathing was established earlier in babies who had cord clamping at 180 s or more.ConclusionSpontaneously breathing babies subjected to DCC have higher oxygen saturation up to 10 min after birth compared to those who have undergone ECC. Spontaneously breathing babies with DCC have lower heart rates compared to ECC until 390 s. Spontaneously breathing babies receiving DCC have early establishment of breathing compared to ECC.Trial registrationISRCTN, 5 April 2016.